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Sample records for braun lipoprotein mutant

  1. Global gene expression of a murein (Braun) lipoprotein mutant of Salmonella enterica serovar Typhimurium by microarray analysis.

    Science.gov (United States)

    Fadl, A A; Galindo, C L; Sha, J; Klimpel, G R; Popov, V L; Chopra, A K

    2006-06-01

    Braun/murein lipoprotein (Lpp) is one of the major outer membrane components of gram-negative enteric bacteria involved in inflammatory responses and septic shock. In previous studies, we reported that two copies of the lipoprotein (lpp) gene (designated as lppA and lppB) existed on the chromosome of Salmonella enterica serovar Typhimurium. Deletion of both lppA and lppB genes rendered Salmonella defective in invasion, motility, induction of cytotoxicity, and production of inflammatory cytokines/chemokines. The lppAB double-knockout (DKO) mutant was attenuated in mice, and animals immunized with this mutant were protected against subsequent challenge with lethal doses of wild-type (wt) S. Typhimurium. To better understand how deletion of the lpp gene might affect Salmonella virulence, we performed global transcriptional profiling of the genes in the wt and the lppAB DKO mutant of S. Typhimurium using microarrays. Our data revealed alterations in the expression of flagellar genes, invasion-associated type III secretion system genes, and transcriptional virulence gene regulators in the lppAB DKO mutant compared to wt S. Typhimurium. These data correlated with the lppAB DKO mutant phenotype and provided possible mechanism(s) of Lpp-associated attenuation in S. Typhimurium. Although these studies were performed in in vitro grown bacteria, our future research will be targeted at global transcriptional profiling of the genes in in vivo grown wt S. Typhimurium and its Lpp mutant.

  2. Comparative Global Gene Expression Profiles of Wild-Type Yersinia pestis CO92 and Its Braun Lipoprotein Mutant at Flea and Human Body Temperatures

    Directory of Open Access Journals (Sweden)

    Cristi L. Galindo

    2010-01-01

    Full Text Available Braun/murein lipoprotein (Lpp is involved in inflammatory responses and septic shock. We previously characterized a Δlpp mutant of Yersinia pestis CO92 and found that this mutant was defective in surviving in macrophages and was attenuated in a mouse inhalation model of plague when compared to the highly virulent wild-type (WT bacterium. We performed global transcriptional profiling of WT Y. pestis and its Δlpp mutant using microarrays. The organisms were cultured at 26 and 37 degrees Celsius to simulate the flea vector and mammalian host environments, respectively. Our data revealed vastly different effects of lpp mutation on the transcriptomes of Y. pestis grown at 37 versus 26C. While the absence of Lpp resulted mainly in the downregulation of metabolic genes at 26C, the Y. pestis Δlpp mutant cultured at 37C exhibited profound alterations in stress response and virulence genes, compared to WT bacteria. We investigated one of the stress-related genes (htrA downregulated in the Δlpp mutant relative to WT Y. pestis. Indeed, complementation of the Δlpp mutant with the htrA gene restored intracellular survival of the Y. pestis Δlpp mutant. Our results support a role for Lpp in Y. pestis adaptation to the host environment, possibly via transcriptional activation of htrA.

  3. Enhancement of natural killer cell activity in healthy subjects by Immulina®, a Spirulina extract enriched for Braun-type lipoproteins

    DEFF Research Database (Denmark)

    Nielsen, Claus Henrik; Balachandran, Premalatha; Christensen, Ole;

    2010-01-01

    Immulina®, a commercial extract of Arthrospira (Spirulina) platensis is a potent activator of THP-1 monocytes and CD4+ T cells IN VITRO and enhances several immunological functions in mice. We further characterized Immulina® by determining that Braun-type lipoproteins are responsible for a major...

  4. Enhancement of natural killer cell activity in healthy subjects by Immulina®, a Spirulina extract enriched for Braun-type lipoproteins

    DEFF Research Database (Denmark)

    Nielsen, Claus Henrik; Balachandran, Premalatha; Christensen, Ole;

    2010-01-01

    Immulina®, a commercial extract of Arthrospira (Spirulina) platensis is a potent activator of THP-1 monocytes and CD4+ T cells IN VITRO and enhances several immunological functions in mice. We further characterized Immulina® by determining that Braun-type lipoproteins are responsible for a major...... portion of the IN VITRO monocyte activation exhibited by this material. In order to understand the effect of Immulina® on NK cell activity, a pilot study was conducted on ten healthy North American individuals who supplemented their diet with Immulina® (400¿mg/day) for seven days. We observed a 40......¿% average increase in the killing of K562 tumor cells by NK cells (p¿...

  5. Dr. Wernher Von Braun

    Science.gov (United States)

    1960-01-01

    On September 8, 1960 President Dwight D. Eisenhower visited Huntsville, Alabama to dedicate a new NASA field center in honor of General George C. Marshall, Eisenhower's wartime colleague and the founder of the famous Marshall Plan for European recover after World War II. The new George C. Marshall Space Flight Center was placed under the control of Dr. Wernher Von Braun shown here talking with President Eisenhower. As parto f his remarks dedicating the center, President Eisenhowe refereed to General Marshall as a 'man of yar, yet a builder of peace'. the Marshall Center's first major assignment including building the huge Saturn V rocket that launched human beings on their first journey to the surface of the moon in 1969.

  6. Grp78 is involved in retention of mutant low density lipoprotein receptor protein in the endoplasmic reticulum

    DEFF Research Database (Denmark)

    Jørgensen, M M; Jensen, Ole Nørregaard; Holst, H U;

    2000-01-01

    The low density lipoprotein (LDL) receptor is responsible for removing the majority of the LDL cholesterol from the plasma. Mutations in the LDL receptor gene cause the disease familial hypercholesterolemia (FH). Approximately 50% of the mutations in the LDL receptor gene in patients with FH lead...... to receptor proteins that are retained in the endoplasmic reticulum (ER). Misfolding of mutant LDL receptors is a probable cause of this ER retention, resulting in no functional LDL receptors at the cell surface. However, the specific factors and mechanisms responsible for retention of mutant LDL...

  7. Transfer of fatty acids from the 1-position of phosphatidyl-ethanolamine to the major outer membrane lipoprotein of E coli

    International Nuclear Information System (INIS)

    The fatty acids esterified to Braun's lipoprotein are derived from the phospholipid pool in E. coli. Mutants lacking acyl-CoA synthetase activity (fadD) incorporated extracellular fatty acids specifically into the 1-position of phosphatidylethanolamine (PtdEtn). This pathway was blocked by chloramphenicol and was depressed by preventing the acylation of the amino terminus of the lipoprotein with globomycin. Transfer of fatty acids to lipoprotein was investigated in fadD mutants harboring hybrid plasmids containing either the lipoprotein gene or a lipoprotein-β-lactamase gene fusion under control of the lactose promoter. Labeling of the 1-position of the PtdEtn pool prior to induction of lipoprotein biosynthesis resulted in the transfer of fatty acids from PtdEtn to the lipoproteins. Induction of lipoprotein synthesis in the presence of exogenous [1-14C]palmitate increased the amount of radioactivity entering the PtdEtn pool and efficiently labeled lipoprotein acyl moieties. Lipoprotein fatty acids derived from the 1-position of PtdEtn were resistant to hydroxylamine hydrolysis, and globomycin reduced the incorporation of exogenous [1-14C]palmitic acid into lipoproteins by 80% suggesting that the fatty acid is attached to the amino terminus. These data illustrate the metabolic relationship between turnover of fatty acids in the 1-position of PtdEtn and the maturation of the major outer membrane lipoprotein

  8. DETECTING LOW DENSITY LIPOPROTEIN RECEPTOR MUTANT GENE OF RABBIT BY PCR

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Many factors playi mportant roles inthe devel-opment of human atherosclerotic lesions,the lead-ing risk factor for atherosclerosis is familial hyper-cholesterolaemia(FH)[1-2].FHis a genetic diseasecharacterized by a deficiency of receptors for lowdensity lipoprotein(LDL)on the plas malemma ofendothelial cells,a high level of serum LDL,andearly development of atherosclerosis[3].WatanabeHeritable Hyperlipidaemic(WHHL)rabbits withunprovoked hypercholesterolaemia,increased bloodlevel of LDL,pronounced atheroscl...

  9. Surface behavior of apolipoprotein A-I and its deletion mutants at model lipoprotein interfaces

    OpenAIRE

    Wang, Libo; Mei, Xiaohu; Atkinson, David; Small, Donald M.

    2014-01-01

    Apolipoprotein A-I (apoA-I) has a great conformational flexibility to exist in lipid-free, lipid-poor, and lipid-bound states during lipid metabolism. To address the lipid binding and the dynamic desorption behavior of apoA-I at lipoprotein surfaces, apoA-I, Δ(185-243)apoA-I, and Δ(1-59)(185-243)apoA-I were studied at triolein/water and phosphatidylcholine/triolein/water interfaces with special attention to surface pressure. All three proteins are surface active to both interfaces lowering th...

  10. DETECTING LOW DENSITY LIPOPROTEIN RECEPTOR MUTANT GENE OF RABBIT BY PCR

    Institute of Scientific and Technical Information of China (English)

    Liu Enqi; Zhao Sihai; Chen Zhenglan; Yang Penghui

    2006-01-01

    Objective Watanabe Heritable Hyperlipidaemic (WHHL) rabbits with low density lipoprotein receptor (LDLr) gene mutation have provided unprecedented opportunities for the study of human atherosclerosis, in order to confirm LDL receptor gene status in rabbits, we developed a simple PCR technique to detect LDL mutations in rabbits. Methods Rabbits genomic DNA were extracted from ear biopsy, and amplified by PCR to detect 12 bp deletion mutation in WHHL rabbits. PCR products were directly digested with BglⅠ, and then applied to polyacrylamide gel electrophoresis. Results PCR products from homozygous LDLr +/+ rabbits generated 2 bands of 212 and 94 bp after BglⅠ digestion, LDLr +/- rabbits generated 3 bands (294, 212, and 94 bp), LDLr -/- animals, however, generated only 1 product (294 bp). Conclusion This modified PCR method is simple and reliable.

  11. Braunes Fettgewebe: Die neue Waffe gegen Adipositas?

    Directory of Open Access Journals (Sweden)

    Fenzl A

    2014-01-01

    Full Text Available Adipositas entsteht, wenn die Energieaufnahme den Energieverbrauch übersteigt. Braunes Fett – im Gegensatz zu weißem Fett – ist darauf ausgerichtet, Energie in Form von Wärmeproduktion (Thermogenese zu verbrauchen. Bei diesem Vorgang wird die Atmungskette von der ATP-Synthese entkoppelt, was durch das Molekül „Uncoupling Protein-1“ (UCP-1 vermittelt wird, welches praktisch nur in braunem Fettgewebe vorkommt. Aufgrund seiner hohen Stoffwechselaktivität und der rezenten Entdeckung, dass aktives braunes Fett auch in Erwachsenen vorkommt, hat dieses Gewebe in den vergangenen Jahren einen hohen Stellenwert in der Adipositasforschung erlangt. In zahlreichen Tiermodellen führt die Aktivierung von braunem Fett oder die Transformation von weißem in braunes Fett (browning zu einer Erhöhung des Energieumsatzes sowie zum Schutz vor Adipositas und metabolischen Komplikationen. Zusätzlich zu klassisch braunem und weißem Fett wurde kürzlich eine neue Fettart beschrieben, die sowohl weiße als auch braune Eigenschaften aufweist – das so genannte „beige“ Fett. Beige Fettzellen kommen zwar primär im weißen Fettgewebe vor, können aber, ähnlich wie braune Adipozyten, thermogenetisch hoch aktiv sein. Es werden laufend neue Faktoren entdeckt, die die Entwicklung und/oder Funktion von beigem bzw. braunem Fett kontrollieren. Die Bemühungen, molekulare Mechanismen und Stoffwechselvorgänge in braunem Fett besser zu verstehen, haben sich noch intensiviert, als man kürzlich mittels FDG-PET-Untersuchungen entdeckte, dass aktives braunes Fettgewebe nicht nur in Erwachsenen vorkommt, sondern auch den Energieverbrauch steigert. Derzeit existieren allerdings noch keine pharmakologischen Ansätze, um die metabolischen Eigenschaften von braunem Fett therapeutisch nutzen zu können, doch das Rennen ist längst im Gange.

  12. The odontological identification of Eva Braun Hitler.

    Science.gov (United States)

    Keiser-Nielsen, S; Strøm, F

    1983-01-01

    On May 7th-9th, 1945, a team of Russian pathologists autopsied several bodies found in and near the Fuehrer Bunker in Berlin; among them, a female body (No. 13) was later identified as that of Eva Braun Hitler (EBH), mainly by means of a gold bridge from the lower right jaw. A postmortem photograph of this bridge also shows a separate gold filling. Data now available on the dental treatment of EBH have permitted the present authors to substantiate that this gold filling also came from the mouth of EBH. Further speculation about the fate of EBH would henceforth seem professionally unfounded.

  13. Victor or Villain? Wernher von Braun and the Space Race

    Science.gov (United States)

    O'Brien, Jason L.; Sears, Christine E.

    2011-01-01

    Set during the Cold War and space race, this historical role-play focuses on Wernher von Braun's involvement in and culpability for the use of slave laborers to produce V-2 rockets for Nazi Germany. Students will grapple with two central questions. Should von Braun have been allowed to emigrate to the United States given his affiliation with the…

  14. The two murein lipoproteins of Salmonella enterica serovar Typhimurium contribute to the virulence of the organism.

    Science.gov (United States)

    Sha, J; Fadl, A A; Klimpel, G R; Niesel, D W; Popov, V L; Chopra, A K

    2004-07-01

    Septic shock due to Salmonella and other gram-negative enteric pathogens is a leading cause of death worldwide. The role of lipopolysaccharide in sepsis is well studied; however, the contribution of other bacterial outer membrane components, such as Braun (murein) lipoprotein (Lpp), is not well defined. The genome of Salmonella enterica serovar Typhimurium harbors two copies of the lipoprotein (lpp) gene. We constructed a serovar Typhimurium strain with deletions in both copies of the lpp gene (lpp1 and lpp2) by marker exchange mutagenesis. The integrity of the cell membrane and the secretion of the effector proteins through the type III secretion system were not affected in the lpp double-knockout mutant. Subsequently, the virulence potential of this mutant was examined in a cell culture system using T84 intestinal epithelial and RAW264.7 macrophage cell lines and a mouse model of salmonellosis. The lpp double-knockout mutant was defective in invading and inducing cytotoxic effects in T84 and RAW264.7 cells, although binding of the mutant to the host cell was not affected when compared to the wild-type (WT) serovar Typhimurium. The motility of the mutant was impaired, despite the finding that the number of flagella was similar in the lpp double knockout mutant and the WT serovar Typhimurium. Deletion in the lpp genes did not affect the intracellular survival and replication of Salmonella in macrophages and T84 cells. Induction of the proinflammatory cytokines tumor necrosis factor alpha and interleukin-8 (IL-8) was significantly reduced in macrophages and T84 cells infected with the lpp double-knockout mutant. The levels of IL-8 remained unaffected in T84 cells when infected with either live or heat-killed WT and lpp mutant, indicating that invasion was not required for IL-8 production and that Toll-like receptor 2 signaling might be affected in the Lpp double-knockout mutant. These effects of the Lpp protein could be restored by complementation of the isogenic

  15. Dr. von Braun and Army Ballistics Missile Agency (ABMA) Group

    Science.gov (United States)

    1959-01-01

    This photograph of Dr. von Braun, shown here to the left of General Bruce Medaris, was taken in the fall of 1959, immediately prior to Medaris' retirement from the Army. At the time, von Braun and his associates worked for the Army Ballistics Missile Agency in Huntsville, Alabama. Those in the photograph have been identified as Ernst Stuhlinger, Frederick von Saurma, Fritz Mueller, Hermarn Weidner, E.W. Neubert (partially hidden), W.A. Mrazek, Karl Heimburg, Arthur Rudolph, Otto Hoberg, von Braun, Oswald Lange, Medaris, Helmut Hoelzer, Hans Maus, E.D. Geissler, Hans Heuter, and George Constan.

  16. Does Braun Enteroenterostomy Reduce Delayed Gastric Emptying After Pancreaticoduodenectomy?

    OpenAIRE

    Zhang, Xu-Feng; Yin, Guo-Zhi; Liu, Qing-Guang; Liu, Xue-Min; Wang, Bo; Yu, Liang; Liu, Si-Nan; Cui, Hong-Ying; Lv, Yi

    2014-01-01

    Abstract Whether an additional Braun enteroenterostomy is necessary in reducing delayed gastric emptying (DGE) after pancreaticoduodenectomy (PD) has not yet been well investigated. Herein, in this retrospective study, 395 consecutive cases of patients undergoing classic PD from 2009 to 2013 were reviewed. Patients with and without Braun enteroenterostomy were compared in preoperative baseline characteristics, surgical procedure, postoperative diagnosis, and morbidity including DGE. The DGE w...

  17. Co-localization of 125I-epidermal growth factor and ferritin-low density lipoprotein in coated pits: a quantitative electron microscopic study in normal and mutant human fibroblasts

    OpenAIRE

    1982-01-01

    Low density lipoprotein (LDL) and epidermal growth factor (EGF) bind to receptors on the surface of human fibroblasts and are internalized in coated vesicles. Each of the ligands has been studied separately by electron microscopy in human fibroblasts using ferritin-LDL as one visual probe and 125I-EGF as a second visual probe. A mutant strain of human fibroblasts (J.D.) has been described in which LDL does not localize to coated pits and hence is not internalized. Because LDL and EGF do not c...

  18. Dr. Space the life of Wernher von Braun

    CERN Document Server

    Ward, Bob

    2013-01-01

    Written by veteran aerospace journalist Bob Ward, who spent years investigating his subject, this biography presents a revealing but even-handed portrait of the father of modern rocketry. As he chronicles Wernher von Braun's life, Ward explodes many myths and misconceptions about the controversial genius who was a hero to some, a villain to others. The picture of von Braun that emerges is of a brilliant scientist with limitless curiosity and a drive to achieve his goals at almost any price from, developing the world's first ballistic missile used against the Allies in World War II to help

  19. Braun-Le Chatelier principle in dissipative thermodynamics

    CERN Document Server

    Pavelka, Michal

    2016-01-01

    Braun-Le Chatelier principle is a fundamental result of equilibrium thermodynamics, showing how stable equilibrium states shift when external conditions are varied. The principle follows from convexity of thermodynamic potential. Analogously, from convexity of dissipation potential it follows how steady non-equilibrium states shift when thermodynamic forces are varied, which is the extension of the principle to dissipative thermodynamics.

  20. Murein lipoprotein is a critical outer membrane component involved in Salmonella enterica serovar typhimurium systemic infection.

    Science.gov (United States)

    Fadl, A A; Sha, J; Klimpel, G R; Olano, J P; Niesel, D W; Chopra, A K

    2005-02-01

    Lipopolysaccharide (LPS) and Braun (murein) lipoprotein (Lpp) are major components of the outer membrane of gram-negative enteric bacteria that function as potent stimulators of inflammatory and immune responses. In a previous paper, we provided evidence that two functional copies of the lipoprotein gene (lppA and lppB) located on the chromosome of Salmonella enterica serovar Typhimurium contributed to bacterial virulence. In this study, we characterized lppA and lppB single-knockout (SKO) mutants and compared them with an lpp double-knockout (DKO) mutant using in vitro and in vivo models. Compared to the lpp DKO mutant, which was nonmotile, the motility of the lpp SKO mutants was significantly increased (73 to 77%), although the level of motility did not reach the level of wild-type (WT) S. enterica serovar Typhimurium. Likewise, the cytotoxicity was also significantly increased when T84 human intestinal epithelial cells and RAW264.7 murine macrophages were infected with the lpp SKO mutants compared to the cytotoxicity when cells were infected with the lpp DKO mutant. The level of interleukin-8 (IL-8) in polarized T84 cells infected with the lppB SKO mutant was significantly higher (two- to threefold higher), reaching the level in cells infected with WT S. enterica serovar Typhimurium, than the level in host cells infected with the lppA SKO mutant. The lpp DKO mutant induced minimal levels of IL-8. Similarly, sera from mice infected with the lppB SKO mutant contained 4.5- to 10-fold-higher levels of tumor necrosis factor-alpha and IL-6; the levels of these cytokines were 1.7- to 3.0-fold greater in the lppA SKO mutant-infected mice than in animals challenged with the lpp DKO mutant. The increased cytokine levels observed with the lppB SKO mutant in mice correlated with greater tissue damage in the livers and spleens of these mice than in the organs of animals infected with the lppA SKO and lpp DKO mutants. Moreover, the lppB SKO mutant-infected mice had increased

  1. Contribution of lipoproteins and lipoprotein processing to endocarditis virulence in Streptococcus sanguinis.

    Science.gov (United States)

    Das, Sankar; Kanamoto, Taisei; Ge, Xiuchun; Xu, Ping; Unoki, Takeshi; Munro, Cindy L; Kitten, Todd

    2009-07-01

    Streptococcus sanguinis is an important cause of infective endocarditis. Previous studies have identified lipoproteins as virulence determinants in other streptococcal species. Using a bioinformatic approach, we identified 52 putative lipoprotein genes in S. sanguinis strain SK36 as well as genes encoding the lipoprotein-processing enzymes prolipoprotein diacylglyceryl transferase (lgt) and signal peptidase II (lspA). We employed a directed signature-tagged mutagenesis approach to systematically disrupt these genes and screen each mutant for the loss of virulence in an animal model of endocarditis. All mutants were viable. In competitive index assays, mutation of a putative phosphate transporter reduced in vivo competitiveness by 14-fold but also reduced in vitro viability by more than 20-fold. Mutations in lgt, lspA, or an uncharacterized lipoprotein gene reduced competitiveness by two- to threefold in the animal model and in broth culture. Mutation of ssaB, encoding a putative metal transporter, produced a similar effect in culture but reduced in vivo competiveness by >1,000-fold. [(3)H]palmitate labeling and Western blot analysis confirmed that the lgt mutant failed to acylate lipoproteins, that the lspA mutant had a general defect in lipoprotein cleavage, and that SsaB was processed differently in both mutants. These results indicate that the loss of a single lipoprotein, SsaB, dramatically reduces endocarditis virulence, whereas the loss of most other lipoproteins or of normal lipoprotein processing has no more than a minor effect on virulence. PMID:19395487

  2. Special Issue on Signal Processing for Mechanical Systems in Honor of Professor Simon Braun

    Science.gov (United States)

    Fassois, Spilios D.

    2016-06-01

    This Special Issue is in honor of a pioneer of the area of Signal Processing for Mechanical Systems and, at the same time, Founding Editor of the Journal of Mechanical Systems and Signal Processing (MSSP), Professor Simon Braun.

  3. Deletion of lolB, Encoding an Outer Membrane Lipoprotein, Is Lethal for Escherichia coli and Causes Accumulation of Lipoprotein Localization Intermediates in the Periplasm

    OpenAIRE

    Tanaka, Kimie; Matsuyama, Shin-ichi; Tokuda, Hajime

    2001-01-01

    Outer membrane lipoproteins of Escherichia coli are released from the inner membrane upon the formation of a complex with a periplasmic chaperone, LolA, followed by localization to the outer membrane. In vitro biochemical analyses revealed that the localization of lipoproteins to the outer membrane generally requires an outer membrane lipoprotein, LolB, and occurs via transient formation of a LolB-lipoprotein complex. On the other hand, a mutant carrying the chromosomal lolB gene under the co...

  4. Familial lipoprotein lipase deficiency

    Science.gov (United States)

    ... medlineplus.gov/ency/article/000408.htm Familial lipoprotein lipase deficiency To use the sharing features on this page, please enable JavaScript. Familial lipoprotein lipase deficiency is a group of rare genetic disorders ...

  5. Lipoprotein lipase deficiency.

    OpenAIRE

    Shankar K; Bava H; Shetty J; Joshi M

    1997-01-01

    A rare case of a 3 month old child with lipoprotein lipase deficiency who presented with bronchopneumonia is reported. After noticing lipaemic serum and lipaemia retinalis, a diagnosis of hyperlipoproteinaemia was considered. Lipoprotein lipase deficiency was confirmed with post heparin lipoprotein lipase enzyme activity estimation.

  6. A process supported by the utility BBPC for analysing Braun-Blanquet data on a personal computer

    Directory of Open Access Journals (Sweden)

    H. Bezuidenhout

    1996-01-01

    Full Text Available Many South African vegetation scientists use utilise the Braun-Blanquet methodology. The main aim of this paper is to describe an affordable, rapid and efficient process for analysing Braun-Blanquet phytosociological data sets on a personal computer. It describes a suite of utilities joining various phases and this makes the entire process possible.

  7. Lipoprotein sorting in bacteria.

    Science.gov (United States)

    Okuda, Suguru; Tokuda, Hajime

    2011-01-01

    Bacterial lipoproteins are synthesized as precursors in the cytoplasm and processed into mature forms on the cytoplasmic membrane. A lipid moiety attached to the N terminus anchors these proteins to the membrane surface. Many bacteria are predicted to express more than 100 lipoproteins, which play diverse functions on the cell surface. The Lol system, composed of five proteins, catalyzes the localization of Escherichia coli lipoproteins to the outer membrane. Some lipoproteins play vital roles in the sorting of other lipoproteins, lipopolysaccharides, and β-barrel proteins to the outer membrane. On the basis of results from biochemical, genetic, and structural studies, we discuss the biogenesis of lipoproteins in bacteria, their importance in cellular functions, and the molecular mechanisms underlying efficient sorting of hydrophobic lipoproteins to the outer membrane through the hydrophilic periplasm. PMID:21663440

  8. Lipoprotein(a)

    DEFF Research Database (Denmark)

    Langsted, Anne; Kamstrup, Pia R; Nordestgaard, Børge G

    2014-01-01

    OBJECTIVE: There are no recommendations in guidelines on measuring lipoprotein(a) in the fasting or nonfasting state, or on the influence of inflammation. We tested the hypotheses that lipoprotein(a) levels change only minimally in response to normal food intake, and to inflammation. Also, we......(a) levels did not change in response to normal food intake: median fasting levels were 17.3 mg/dL, while median levels at 3-4 h since last meal were 19.4 mg/dL(p = 0.38). Lipoprotein(a) levels increased minimally with increasing levels of C-reactive protein(CRP): median lipoprotein(a) levels at CRP <1 mg...... tested whether normal food intake or inflammation influenced lipoprotein(a)'s ability to predict ischemic heart disease. METHODS: We studied 34 829 individuals from the Danish general population using the Copenhagen General Population Study and the Copenhagen City Heart Study. RESULTS: Lipoprotein...

  9. Defective Lipoprotein Sorting Induces lolA Expression through the Rcs Stress Response Phosphorelay System

    OpenAIRE

    Tao, Kazuyuki; Narita, Shin-ichiro; Tokuda, Hajime

    2012-01-01

    The Escherichia coli LolA protein is a lipoprotein-specific chaperone that carries lipoproteins from the inner to the outer membrane. A dominant negative LolA mutant, LolA(I93C/F140C), in which both 93Ile and 140Phe are replaced by Cys, binds tightly to the lipoprotein-dedicated ABC transporter LolCDE complex on the inner membrane and therefore inhibits the detachment of outer membrane-specific lipoproteins from the inner membrane. We found that the expression of this mutant strongly induced ...

  10. Dr. von Braun and Dr. Stuhlinger With a Model of the Nuclear-Electric Vehicles

    Science.gov (United States)

    2004-01-01

    In this photo, taken at the Walt Disney Studios in California, Dr. Wernher von Braun and Dr. Ernst Stuhlinger are shown discussing the concepts of nuclear-electric spaceships designed to undertake the mission to the planet Mars. As a part of the Disney 'Tomorrowland' series on the exploration of space, the nuclear-electric vehicles were shown in the last three television films, entitled 'Mars and Beyond,' which first aired in December 1957.

  11. Die Künstlerin als Produzentin – Johanna Braun im Gespräch

    Directory of Open Access Journals (Sweden)

    Johanna Braun

    2014-03-01

    Full Text Available Die Wiener Künstlerin Johanna Braun ist eine der prononciertesten Vertreterinnen eigenaktiver, kuratorischer Tätigkeit der künstlerisch Schaffenden. Mit zahlreichen internationalen Projekten hat sie die Richtigkeit ihrer Haltung immer wieder bewiesen – und sich dabei nicht selten an den ihr fragwürdig vorkommenden Konventionen kuratorischen Selbstverständnisses kritisch abgearbeitet. – Freimütig und provokant hat sie auf Fragen des MEDIENIMPULSE-Redakteurs Thomas Ballhausen geantwortet.

  12. Floral and Seed Variability Patterns among Ethiopian Mustard (B. carinata A. Braun) of East Africa

    OpenAIRE

    Adeniji, OT.; A. Aloyce, A.

    2012-01-01

    In East Africa, Ethiopian mustard (Brassica carinata A. Braun) is cultivated primarily for its leaves, but in Ethiopia preference is high for oil in the seed. Dual purpose importance of the seeds for planting and for oil suggests the need to improve seed production efficiency through understanding variation pattern for floral morphology and seed characters. We investigated genetic diversity and correlations for floral and seed characteristics among 14 accessions of Ethiopian mustard to improv...

  13. la teoría del desarrollo desigual de Óscar Braun. Un análisis critico

    Directory of Open Access Journals (Sweden)

    Wright Phil

    1979-12-01

    Full Text Available

    En este análisis crítico de la teoría del intercambio desigual de Oscar Braun, intentamos movernos consistentemente a través de un número de etapas analíticas distintas. Estas etapas son: a una discusión sobre el objeto del conocimiento en Braun, sin las restricciones de su propia problemática (sección 3; b una confrontación del objeto del conocímiento en Braun con el objeto real o concreto (sección4, y c una crítica a] objeto del conocimiento en Braun (secciones 2 y 5. La crítica del objeto del conocimiento en Braun se divide en dos partes ya que tratamos con dos problemas analíticos distintos: a la teoría del intercambio desigual puede estar representada como una teoría del imperialismo, y b la naturaleza del objeto del conocimiento contenida en la teoría del intercambio desigual de Braun es la que causa los problemas y la que lo lleva a constituirla como una teoría del imperialismo.

  14. Randomized trial comparing episiotomies with Braun-Stadler episiotomy scissors and EPISCISSORS-60®

    Directory of Open Access Journals (Sweden)

    Sawant G

    2015-06-01

    Full Text Available Ganpat Sawant, Divya Kumar Dr DY Patil Medical College and Hospital, Nerul, Navi Mumbai, India Introduction: Episiotomy angle is a crucial factor in causation of obstetric anal sphincter injuries (OASIS, which are the major cause of female bowel incontinence. Sutured episiotomies angled too close to the midline (<30 degree or too far away from the midline (.60 degree fail to unload the perineum sufficiently and predispose to OASIS. A 25-degree post-delivery episiotomy suture angle has a 10% risk of OASIS while 45-degree episiotomy is associated with 0.5% risk. To account for perineal distension at crowning, a 60-degree episiotomy incision is required to achieve 43–50 degree suture angles. We compared episiotomy suture angles with commonly used Braun-Stadler episiotomy scissors with the new fixed angle EPISCISSORS-60®. Methods: Ethical approval was obtained. A prospective cluster randomization design was chosen. Thirty-one patients were required in each group for a 12-degree difference with power at 90% and 5% significance. Sutured episiotomy angles and post-delivery linear distance from caudal end of the sutured episiotomy to the anus were measured with protractors and rulers. Two-tailed t-tests were used to compare the two groups. Results: Thirty-one nulliparae had episiotomies with EPISCISSORS-60®, 32 with Braun-Stadler. Mean age (25 versus 24.8 years was similar. EPISCISSORS-60® episiotomies were angled 12 degrees more laterally away from the anus compared to Braun-Stadler (40.6 degrees, 95% confidence interval [CI] ±2, interquartile range [IQR] 35–45 versus 28.3 degrees, 95% CI ±2, IQR 25–30, P<0.0001. The post-delivery linear distance from caudal end of the sutured episiotomy to the anus was 15 mm more with the EPISCISSORS-60® compared to Braun-Stadler (35 mm, 95% CI ±2.2, IQR =30–39 versus 19.5; 95% CI ±1.3, IQR =14.75–22.25 P<0.0001. EPISCISSORS-60® episiotomies measured longer (47 mm versus 40 mm, P<0.0001. There were

  15. Hydrophobic surface patches on LolA of Pseudomonas aeruginosa are essential for lipoprotein binding.

    Science.gov (United States)

    Remans, Kim; Pauwels, Kris; van Ulsen, Peter; Buts, Lieven; Cornelis, Pierre; Tommassen, Jan; Savvides, Savvas N; Decanniere, Klaas; Van Gelder, Patrick

    2010-09-01

    Many lipoproteins reside in the outer membrane (OM) of Gram-negative bacteria, and their biogenesis is dependent on the Lol (localization of lipoproteins) system. The periplasmic chaperone LolA accepts OM-destined lipoproteins that are released from the inner membrane by the LolCDE complex and transfers them to the OM receptor LolB. The exact nature of the LolA-lipoprotein complex is still unknown. The crystal structure of Escherichia coli LolA features an open beta-barrel covered by alpha helices that together constitute a hydrophobic cavity, which would allow the binding of one acyl chain. However, OM lipoproteins contain three acyl chains, and the stoichiometry of the LolA-lipoprotein complex is 1:1. Here we present the crystal structure of Pseudomonas aeruginosa LolA that projects clear hydrophobic surface patches. Since these patches are large enough to accommodate acyl chains, their role in lipoprotein binding was investigated. Several LolA mutant proteins were created, and their functionality was assessed by studying their capacity to release lipoproteins produced in sphaeroplasts. Interruption of the largest hydrophobic patch completely destroyed the lipoprotein-releasing capacity of LolA, while interruption of smaller patches apparently reduced efficiency. Thus, the results show a new lipoprotein transport model that places (some of) the acyl chains on the hydrophobic surface patches. PMID:20620146

  16. Albert Einstein and Wernher von Braun - the two great German-American physicists seen in a historical perspective.

    Science.gov (United States)

    Winterberg, Friedwardt

    2008-04-01

    It was Albert Einstein who for the first time changed our view of the universe to be a non-euclidean curved space-time. And it was Wernher von Braun who blazed the trail to take us into this universe, leaving for the first time the gravitational field of our planet earth, with the landing a man on the moon the greatest event in human history. Both these great physicists did this on the shoulders of giants. Albert Einstein on the shoulders of his landsman, the mathematician Bernhard Riemann, and Wernher von Braun on the shoulders of Goddard and Oberth. Both Einstein and von Braun made a Faustian pact with the devil, von Braun by accepting research funds from Hitler, and Einstein by urging Roosvelt to build the atom bomb (against Hitler). Both of these great men later regretted the use of their work for the killing of innocent bystanders, even though in the end the invention of nuclear energy and space flight is for the benefit of man. Their example serves as a warning for all of us. It can be formulated as follows: ``Can I in good conscience accept research funds from the military to advance scientific knowledge, for weapons developed against an abstract enemy I never have met in person?'' Weapons if used do not differentiate between the scientist, who invented these weapons, and the non-scientist.

  17. Lipoprotein marker for hypertriglyceridemia

    Science.gov (United States)

    Cubicciotti, Roger S.; Karu, Alexander E.; Krauss, Ronald M.

    1986-01-01

    Methods and compositions are provided for the detection of a particular low density lipoprotein which has been found to be a marker for patients suffering from type IV hypertriglyceridemia. A monoclonal antibody capable of specifically binding to a characteristic epitopic site on this LDL subspecies can be utilized in a wide variety of immunoassays. Hybridoma cell line SPL.IVA5A1 was deposited at the American Type Culture Collection on Mar. 29, 1984, and granted accession no. HB 8535.

  18. Congenital β-lipoprotein deficiency

    NARCIS (Netherlands)

    Buchem, F.S.P. van; Pol, G.; Gier, J. de; Böttcher, C.J.F.; Pries, C.

    1966-01-01

    There are several degrees of β-lipoprotein deficiency. If there is no β-lipoprotein present, or if there are only traces of it, the Bassen-Kornzweig syndrome develops. A constant feature of this syndrome is disturbed fat absorption with accumulation of fat in the epithelium of intestinal mucosa and

  19. Phytosterols, Phytostanols, and Lipoprotein Metabolism

    Directory of Open Access Journals (Sweden)

    Helena Gylling

    2015-09-01

    Full Text Available The efficacy of phytosterols and phytostanols added to foods and food supplements to obtain significant non-pharmacologic serum and low density lipoprotein (LDL cholesterol reduction is well documented. Irrespective of age, gender, ethnic background, body weight, background diet, or the cause of hypercholesterolemia and, even added to statin treatment, phytosterols and phytostanols at 2 g/day significantly lower LDL cholesterol concentration by 8%–10%. They do not affect the concentrations of high density lipoprotein cholesterol, lipoprotein (a or serum proprotein convertase subtilisin/kexin type 9. In some studies, phytosterols and phytostanols have modestly reduced serum triglyceride levels especially in subjects with slightly increased baseline concentrations. Phytosterols and phytostanols lower LDL cholesterol by displacing cholesterol from mixed micelles in the small intestine so that cholesterol absorption is partially inhibited. Cholesterol absorption and synthesis have been carefully evaluated during phytosterol and phytostanol supplementation. However, only a few lipoprotein kinetic studies have been performed, and they revealed that LDL apoprotein B-100 transport rate was reduced. LDL particle size was unchanged, but small dense LDL cholesterol concentration was reduced. In subjects with metabolic syndrome and moderate hypertriglyceridemia, phytostanols reduced not only non- high density lipoprotein (HDL cholesterol concentration but also serum triglycerides by 27%, and reduced the large and medium size very low density lipoprotein particle concentrations. In the few postprandial studies, the postprandial lipoproteins were reduced, but detailed studies with apoprotein B-48 are lacking. In conclusion, more kinetic studies are required to obtain a more complete understanding of the fasting and postprandial lipoprotein metabolism caused by phytosterols and phytostanols. It seems obvious, however, that the most atherogenic lipoprotein

  20. Agronomic performance for biodiesel production potential of Brassica carinata A. Braun in Mediterranean marginal areas

    Directory of Open Access Journals (Sweden)

    Francesco Montemurro

    2016-03-01

    Full Text Available Brassicaceae are promising oil feedstock for cultivation in centralsouthern Italy. Therefore, a two-year investigation on Brassica carinata A. Braun (cv. CT 204 was carried out in three sites of Apulia region [Site 1, Alberobello - Murgia foreland; Site 2, Troia (Foggia - Daunian sub-Apennines; Site 3, Monteroni (Lecce - Area of Salento], and in one site of Basilicata region (Site 4, Hill of Matera. The aim was to identify site-specific management practices [by comparing minimum vs conventional tillage, low sowing density vs high sowing density; different levels of nitrogen (N supply and organic fertilisers] in the four different marginal areas, to achieve optimum yield performance for biodiesel prospective production. The crop showed a good adaptability in the study sites, and the highest N level positively influenced the yield performance in Sites 1, 2 and 3. Moreover, the reduction of mechanical operations (minimum tillage did not negatively influence crop production and seed oil content. The highest density of sowing tested determined the best crop performance in Site 3, particularly showing the maximum seed oil content with the lowest N supply. Finally, in Site 4 the compost mixed with mineral N fertiliser as well as the sewage sludge from urban wastewater determined productive results comparable to those obtained with mineral fertiliser, evidencing that organic fertilisers could (partially or completely substitute the mineral one for this crop in the study site. On the whole, seed yield and oil content showed a potential for biodiesel production of Brassica carinata cultivated with site-specific agronomic techniques in four different marginal areas of Southern Italy, suggesting it can be likely achieved the crop environmental adaptation.

  1. Floral and Seed Variability Patterns among Ethiopian Mustard (B. carinata A. Braun of East Africa

    Directory of Open Access Journals (Sweden)

    Adeniji, OT.

    2012-01-01

    Full Text Available In East Africa, Ethiopian mustard (Brassica carinata A. Braun is cultivated primarily for its leaves, but in Ethiopia preference is high for oil in the seed. Dual purpose importance of the seeds for planting and for oil suggests the need to improve seed production efficiency through understanding variation pattern for floral morphology and seed characters. We investigated genetic diversity and correlations for floral and seed characteristics among 14 accessions of Ethiopian mustard to improve seed set and yield. Field trials were conducted during 2008 and 2009; flowers were examined for short stamen height, long stamen height, pistil height, and silliqua for seed weight, seeds/silliqua and silliqua/plant. Results were largely consistent between years, indicating that the variation measured was mainly controlled by genetic factors. High genetic variation for seed characters and reproductive phenology among the accessions was noted. The number of days to appearance of flowers showed high discriminatory ability among the accessions. A wide continuous variation was observed among accessions for anther-stigma separation. Accessions 1, 3 and 14 were identified as early flowering. A significant and positive correlation coefficient between short stamen height and seed weight indicated a substantial complementation among these characters for seed yield improvement. The short stamen height is a good indicator for selection in favour of seed commercialization and indices for selection of pollen parent for seed yield improvement. Accessions 5, 7, 14, 16 and 22 are best for multiple characters and are recommended for seed production for any of the seasons in Arusha, Tanzania.

  2. Ion mobility analysis of lipoproteins

    Science.gov (United States)

    Benner, W. Henry; Krauss, Ronald M.; Blanche, Patricia J.

    2007-08-21

    A medical diagnostic method and instrumentation system for analyzing noncovalently bonded agglomerated biological particles is described. The method and system comprises: a method of preparation for the biological particles; an electrospray generator; an alpha particle radiation source; a differential mobility analyzer; a particle counter; and data acquisition and analysis means. The medical device is useful for the assessment of human diseases, such as cardiac disease risk and hyperlipidemia, by rapid quantitative analysis of lipoprotein fraction densities. Initially, purification procedures are described to reduce an initial blood sample to an analytical input to the instrument. The measured sizes from the analytical sample are correlated with densities, resulting in a spectrum of lipoprotein densities. The lipoprotein density distribution can then be used to characterize cardiac and other lipid-related health risks.

  3. Aerosol preparation of intact lipoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Benner, W. Henry (Danville, CA); Krauss, Ronald M (Berkeley, CA); Blanche, Patricia J (Berkeley, CA)

    2012-01-17

    A medical diagnostic method and instrumentation system for analyzing noncovalently bonded agglomerated biological particles is described. The method and system comprises: a method of preparation for the biological particles; an electrospray generator; an alpha particle radiation source; a differential mobility analyzer; a particle counter; and data acquisition and analysis means. The medical device is useful for the assessment of human diseases, such as cardiac disease risk and hyperlipidemia, by rapid quantitative analysis of lipoprotein fraction densities. Initially, purification procedures are described to reduce an initial blood sample to an analytical input to the instrument. The measured sizes from the analytical sample are correlated with densities, resulting in a spectrum of lipoprotein densities. The lipoprotein density distribution can then be used to characterize cardiac and other lipid-related health risks.

  4. Real time analysis of lipoprotein transfer from LolA to LolB by means of surface plasmon resonance.

    Science.gov (United States)

    Tsukahara, Jun; Narita, Shin-Ichiro; Tokuda, Hajime

    2009-09-17

    Lipoproteins of Escherichia coli are sorted to the outer membrane through a pathway composed of five Lol proteins. LolA transports lipoproteins released from the inner membrane by LolCDE to LolB on the outer membrane via the periplasm. Interaction between LolA and LolB was speculated to be strong when LolA binds lipoprotein. However, due to a lack of a sensitive method, the kinetics of this reaction have not been examined in detail. We report here the detection of lipoprotein transfer in real time by means of surface plasmon resonance. The kinetic parameters of lipoprotein transfer were determined with wild-type LolA and a mutant defective in it. PMID:19716823

  5. Lipoprotein(a) and dietary proteins: casein lowers lipoprotein(a) concentrations as compared with soy protein1-3

    DEFF Research Database (Denmark)

    Nilausen, Karin Johanne; Meinertz, H.

    1999-01-01

    Lipoprotein(a), plasma lipoproteins, dietary proteins, soy protein, casein, liquid-formula, coronary artery disease, men, Denmark......Lipoprotein(a), plasma lipoproteins, dietary proteins, soy protein, casein, liquid-formula, coronary artery disease, men, Denmark...

  6. Revisiting the gram-negative lipoprotein paradigm

    Science.gov (United States)

    The processing of lipoproteins (lpps) in Gram-negative bacteria is generally considered to be an essential pathway. Mature lipoproteins in these bacteria are triacylated, with the final fatty acid addition performed by Lnt, an apolipoprotein n-acyltransferase. The mature lipoproteins are then sorted...

  7. Structural studies on lipoprotein lipase

    International Nuclear Information System (INIS)

    The structure of lipoprotein lipase is not known. The lack of information on its primary sequence has been due to the inability of preparing it in homogeneous and stable form. This research has focused on the structural characterization of lipoprotein lipase. The first approach taken was to develop a purification method using bovine milk and affinity chromatography on heparin-Sepharose. The protein obtained was a heterogeneous peak with the activity shifted towards the trailing edge fractions. These fractions only presented a 55 Kdalton band on polyacrylamide gel electrophoresis. Monoclonal antibodies against this band detected an endogenous, phenyl methane sulfonyl fluoride-sensitive protease responsible for the presence of lower molecular weight fragments. The second approach was to label the lipoprotein lipase with a radioactive, active site, directed probe. After incubation and affinity chromatography a complex [3H]inhibitor enzyme was isolated with a stoichiometry of 1.00 +/- 0.2. The complex was digested with CNBr and the insoluble peptides at low ionic strength (>90% [3H]dpm) were used for further purification. Differential extraction of the [3H]-peptide, digestion with S. aureus V8 protease, and high performance liquid chromatography yielded a hexapeptide with a composition consistent with the consensus sequence of the active site peptides of many serine-esterase. This and the kinetic data imply this being the mechanism of action for lipoprotein lipase

  8. Butter, margarine and serum lipoproteins.

    NARCIS (Netherlands)

    Zock, P.L.; Katan, M.B.

    1997-01-01

    Intake of trans fatty acids unfavorably affects blood lipoproteins. As margarines are a major source of trans, claims for the advantages of margarines over butter need to be scrutinized. Here we review dietary trials that directly compared the effects of butter and margarine on blood lipids. We iden

  9. [Lipoprotein receptors. Old acquaintances and newcomers].

    Science.gov (United States)

    Ducobu, J

    1997-02-01

    Lipoprotein receptors are plasma membrane proteins of high affinity which interact with circulating lipoprotein particles. The well characterized LDL receptor continues to be analysed and some new findings on its intracellular mechanisms of action have emerged. New lipoprotein receptors have recently been described: the chylomicron remnant receptor or LDL-related protein (LRP), the lipolysis stimulated receptor (LSR), the very low density lipoprotein receptor (VLDLR), the HDL receptor (HDLR) and the scavenger receptor (SR). The molecular details of the receptors will facilitate the development of new therapeutic means to improve receptor-mediated clearance of lipoproteins.

  10. Effects of hormones on lipids and lipoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, R.M.

    1991-12-01

    Levels of plasma lipids and lipoproteins are strong predictors for the development of atherosclerotic cardiovascular disease in postmenopausal women. In women, as in men, numerous factors contribute to variations in plasma lipoproteins that may affect cardiovascular disease risk. These include age, dietary components, adiposity, genetic traits, and hormonal changes. Each of these factors may operate to varying degrees in determining changes in plasma lipoprotein profiles accompanying menopause- Cross-sectional and longitudinal studies have suggested increases in levels of cholesterol, low density lipoproteins (LDL) and triglyceride-rich lipoproteins associated with menopause. High density lipoproteins (HDL), which are higher in women than men and are thought to contribute to relative protection of premenopausal women from cardiovascular disease, remain relatively constant in the years following menopause, although small, and perhaps transient reductions in the HDL{sub 2} subfraction have been reported in relation to reduced estradiol level following menopause. Despite these associations, it has been difficult to determine the role of endogenous hormones in influencing the plasma lipoproteins of postmenopausal women. In principle, the effects of hormone replacement should act to reverse any alterations in lipoprotein metabolism that are due to postmenopausal hormone changes. While there may be beneficial effects on lipoproteins, hormone treatment does not restore a premenopausal lipoprotein profile. Furthermore, it is not dear to what extent exogenous hormone-induced lipoprotein changes contribute to the reduced incidence of cardiovascular disease with hormone replacement therapy.

  11. Biogenesis and Membrane Targeting of Lipoproteins.

    Science.gov (United States)

    Narita, Shin-Ichiro; Tokuda, Hajime

    2010-09-01

    Bacterial lipoproteins represent a unique class of membrane proteins, which are anchored to membranes through triacyl chains attached to the amino-terminal cysteine. They are involved in various functions localized in cell envelope. Escherichia coli possesses more than 90 species of lipoproteins, most of which are localized in the outer membrane, with others being in the inner membrane. All lipoproteins are synthesized in the cytoplasm with an N-terminal signal peptide, translocated across the inner membrane by the Sec translocon to the periplasmic surface of the inner membrane, and converted to mature lipoproteins through sequential reactions catalyzed by three lipoprotein-processing enzymes: Lgt, LspA, and Lnt. The sorting of lipoproteins to the outer membrane requires a system comprising five Lol proteins. An ATP-binding cassette transporter, LolCDE, initiates the sorting by mediating the detachment of lipoproteins from the inner membrane. Formation of the LolA-lipoprotein complex is coupled to this LolCDE-dependent release reaction. LolA accommodates the amino-terminal acyl chain of lipoproteins in its hydrophobic cavity, thereby generating a hydrophilic complex that can traverse the periplasmic space by diffusion. Lipoproteins are then transferred to LolB on the outer membrane and anchored to the inner leaflet of the outer membrane by the action of LolB. In contrast, since LolCDE does not recognize lipoproteins possessing Asp at position +2, these lipoproteins remain anchored to the inner membrane. Genes for Lol proteins are widely conserved among gram-negative bacteria, and Lol-mediated outer membrane targeting of lipoproteins is considered to be the general lipoprotein localization mechanism. PMID:26443779

  12. Small-molecule inhibitors of gram-negative lipoprotein trafficking discovered by phenotypic screening.

    Science.gov (United States)

    McLeod, Sarah M; Fleming, Paul R; MacCormack, Kathleen; McLaughlin, Robert E; Whiteaker, James D; Narita, Shin-Ichiro; Mori, Makiko; Tokuda, Hajime; Miller, Alita A

    2015-03-01

    In Gram-negative bacteria, lipoproteins are transported to the outer membrane by the Lol system. In this process, lipoproteins are released from the inner membrane by the ABC transporter LolCDE and passed to LolA, a diffusible periplasmic molecular chaperone. Lipoproteins are then transferred to the outer membrane receptor protein, LolB, for insertion in the outer membrane. Here we describe the discovery and characterization of novel pyridineimidazole compounds that inhibit this process. Escherichia coli mutants resistant to the pyridineimidazoles show no cross-resistance to other classes of antibiotics and map to either the LolC or LolE protein of the LolCDE transporter complex. The pyridineimidazoles were shown to inhibit the LolA-dependent release of the lipoprotein Lpp from E. coli spheroplasts. These results combined with bacterial cytological profiling are consistent with LolCDE-mediated disruption of lipoprotein targeting to the outer membrane as the mode of action of these pyridineimidazoles. The pyridineimidazoles are the first reported inhibitors of the LolCDE complex, a target which has never been exploited for therapeutic intervention. These compounds open the door to further interrogation of the outer membrane lipoprotein transport pathway as a target for antimicrobial therapy. PMID:25583975

  13. A More Flexible Lipoprotein Sorting Pathway

    OpenAIRE

    Chahales, Peter; Thanassi, David G.

    2015-01-01

    Lipoprotein biogenesis in Gram-negative bacteria occurs by a conserved pathway, each step of which is considered essential. In contrast to this model, LoVullo and colleagues demonstrate that the N-acyl transferase Lnt is not required in Francisella tularensis or Neisseria gonorrhoeae. This suggests the existence of a more flexible lipoprotein pathway, likely due to a modified Lol transporter complex, and raises the possibility that pathogens may regulate lipoprotein processing to modulate int...

  14. Revisiting the Gram-Negative Lipoprotein Paradigm

    OpenAIRE

    LoVullo, Eric D.; Wright, Lori F.; Isabella, Vincent; Huntley, Jason F.; Pavelka, Martin S.

    2015-01-01

    The processing of lipoproteins (Lpps) in Gram-negative bacteria is generally considered an essential pathway. Mature lipoproteins in these bacteria are triacylated, with the final fatty acid addition performed by Lnt, an apolipoprotein N-acyltransferase. The mature lipoproteins are then sorted by the Lol system, with most Lpps inserted into the outer membrane (OM). We demonstrate here that the lnt gene is not essential to the Gram-negative pathogen Francisella tularensis subsp. tularensis str...

  15. A more flexible lipoprotein sorting pathway.

    Science.gov (United States)

    Chahales, Peter; Thanassi, David G

    2015-05-01

    Lipoprotein biogenesis in Gram-negative bacteria occurs by a conserved pathway, each step of which is considered essential. In contrast to this model, LoVullo and colleagues demonstrate that the N-acyl transferase Lnt is not required in Francisella tularensis or Neisseria gonorrhoeae. This suggests the existence of a more flexible lipoprotein pathway, likely due to a modified Lol transporter complex, and raises the possibility that pathogens may regulate lipoprotein processing to modulate interactions with the host. PMID:25755190

  16. Lipoprotein lipase increases low density lipoprotein retention by subendothelial cell matrix.

    OpenAIRE

    Saxena, U; Klein, M. G.; Vanni, T M; Goldberg, I J

    1992-01-01

    Lipoprotein lipase (LPL), the rate-limiting enzyme for hydrolysis of plasma lipoprotein triglycerides, is a normal constituent of the arterial wall. We explored whether LPL affects (a) lipoprotein transport across bovine aortic endothelial cells or (b) lipoprotein binding to subendothelial cell matrix (retention). When bovine milk LPL was added to endothelial cell monolayers before addition of 125I-labeled LDL, LDL transport across the monolayers was unchanged; but, at all concentrations of L...

  17. LIPOPROTEIN LIPASE RELEASES ESTERIFIED OXYLIPINS FROM VERY LOW-DENSITY LIPOPROTEINS.

    Science.gov (United States)

    Defects in lipoprotein metabolism alter the lipoprotein distribution of oxidized PUFAs, and we speculate that lipoprotein lipase (LpL) is a determinant in the release of VLDL-associated oxylipins. Here, using 12 wk old normolipidemic (lean) and hyperlipidemic (obese) Zucker-rats, we measured PUFA al...

  18. Diagnostic markers based on a computational model of lipoprotein metabolism

    NARCIS (Netherlands)

    Schalkwijk, D.B. van; Ommen, B. van; Freidig, A.P.; Greef, J. van der; Graaf, A.A. de

    2011-01-01

    Abstract Background: Dyslipidemia is an important risk factor for cardiovascular disease and type II diabetes. Lipoprotein diagnostics, such as LDL cholesterol and HDL cholesterol, help to diagnose these diseases. Lipoprotein profile measurements could improve lipoprotein diagnostics, but interpreta

  19. Peroxisome Proliferator Activated Receptors and Lipoprotein Metabolism

    NARCIS (Netherlands)

    Kersten, A.H.

    2008-01-01

    Plasma lipoproteins are responsible for carrying triglycerides and cholesterol in the blood and ensuring their delivery to target organs. Regulation of lipoprotein metabolism takes place at numerous levels including via changes in gene transcription. An important group of transcription factors that

  20. Analýza komunikačního mixu vybraného výrobku společnosti B. Braun Medical

    OpenAIRE

    Dykastová, Aneta

    2012-01-01

    This thesis is focused on communication mix analysis of the Einstein Vision 3D laparoscopic system. It is a product of B. Braun Medical Company, which specializes in importing and distributing of devices, instruments, tools and equipment for anesthesia, intensive medicine, cardiology, surgery and extra corporeal blood treatment. The thesis is divided into two parts, theoretical and practical. The first part describes theory of marketing with the emphasis on the communication mix. The second p...

  1. Computational studies of plasma lipoprotein lipids.

    Science.gov (United States)

    Pan, Lurong; Segrest, Jere P

    2016-10-01

    Plasma lipoproteins are macromolecular assemblies of proteins and lipids found in the blood. The lipid components of lipoproteins are amphipathic lipids such as phospholipids (PLs), and unesterified cholesterols (UCs) and hydrophobic lipids such as cholesteryl esters (CEs) and triglycerides (TGs). Since lipoproteins are soft matter supramolecular assemblies easily deformable by thermal fluctuations and they also exist in varying densities and protein/lipid components, a detailed understanding of their structure/function is experimentally difficult. Molecular dynamics (MD) simulation has emerged as a particularly promising way to explore the structure and dynamics of lipoproteins. The purpose of this review is to survey the current status of computational studies of the lipid components of the lipoproteins. Computational studies aim to explore three levels of complexity for the 3-dimensional structural dynamics of lipoproteins at various metabolic stages: (i) lipoprotein particles consist of protein with minimal lipid; (ii) lipoprotein particles consist of PL-rich discoidal bilayer-like lipid particles; (iii) mature circulating lipoprotein particles consist of CE-rich or TG-rich spheroidal lipid-droplet-like particles. Due to energy barriers involved in conversion between these species, other biomolecules also participate in lipoprotein biological assembly. For example: (i) lipid-poor apolipoprotein A-I (apoA-I) interacts with ATP-binding cassette transporter A1 (ABCA1) to produce nascent discoidal high density lipoprotein (dHDL) particles; (ii) lecithin-cholesterol acyltransferase (LCAT) mediates the conversion of UC to CE in dHDL, driving spheroidal HDL (sHDL) formation; (iii) transfer proteins, cholesterol ester transfer protein (CETP) and phospholipid transfer protein (PLTP), transfer both CE and TG and PL, respectively, between lipoprotein particles. Computational studies have the potential to explore different lipoprotein particles at each metabolic stage in

  2. Roles of the protruding loop of factor B essential for the localization of lipoproteins (LolB) in the anchoring of bacterial triacylated proteins to the outer membrane.

    Science.gov (United States)

    Hayashi, Yumi; Tsurumizu, Ryoji; Tsukahara, Jun; Takeda, Kazuki; Narita, Shin-ichiro; Mori, Makiko; Miki, Kunio; Tokuda, Hajime

    2014-04-11

    The Lol system comprising five Lol proteins, LolA through LolE, sorts Escherichia coli lipoproteins to outer membranes. The LolCDE complex, an ATP binding cassette transporter in inner membranes, releases outer membrane-specific lipoproteins in an ATP-dependent manner, causing formation of the LolA-lipoprotein complex in the periplasm. LolA transports lipoproteins through the periplasm to LolB on outer membranes. LolB is itself a lipoprotein anchored to outer membranes, although the membrane anchor is functionally dispensable. LolB then localizes lipoproteins to outer membranes through largely unknown mechanisms. The crystal structure of LolB is similar to that of LolA, and it possesses a hydrophobic cavity that accommodates acyl chains of lipoproteins. To elucidate the molecular function of LolB, a periplasmic version of LolB, mLolB, was mutagenized at various conserved residues. Despite the lack of acyl chains, most defective mutants were insoluble. However, a derivative with glutamate in place of leucine 68 was soluble and unable to localize lipoproteins to outer membranes. This leucine is present in a loop protruding from mLolB into an aqueous environment, and no analogous loop is present in LolA. Thus, leucine 68 was replaced with other residues. Replacement by acidic, but not hydrophobic, residues generated for the first time mLolB derivatives that can accept but cannot localize lipoproteins to outer membranes. Moreover, deletion of the leucine with neighboring residues impaired the lipoprotein receptor activity. Based on these observations, the roles of the protruding loop of LolB in the last step of lipoprotein sorting are discussed. PMID:24569999

  3. Understanding Lipoproteins as Transporters of Cholesterol and Other Lipids

    Science.gov (United States)

    Biggerstaff, Kyle D.; Wooten, Joshua S.

    2004-01-01

    A clear picture of lipoprotein metabolism is essential for understanding the pathophysiology of atherosclerosis. Many students are taught that low-density lipoprotein-cholesterol is "bad" and high-density lipoprotein-cholesterol is "good." This misconception leads to students thinking that lipoproteins are types of cholesterol rather than…

  4. Low-density lipoprotein analysis in microchip capillary electrophoresis systems

    NARCIS (Netherlands)

    Ceriotti, Laura; Shibata, Takayuki; Folmer, Britta; Weiller, Bruce H.; Roberts, Matthew A.; De Rooij, Nico F.; Verpoorte, Elisabeth

    2002-01-01

    Due to the mounting evidence for altered lipoprotein and cholesterol-lipoprotein content in several disease states, there has been an increasing interest in analytical methods for lipoprotein profiling for diagnosis. The separation of low- and high-density lipoproteins (LDL and HDL, respectively) ha

  5. Resultados neonatais no parto vaginal espontâneo comparados aos dos partos com fórcipe de Simpson-Braun em primíparas Neonatal outcome of spontaneous deliveries as compared to Simpson-Braun forceps deliveries in nulliparous women

    Directory of Open Access Journals (Sweden)

    Belmiro Gonçalves Pereira

    2004-02-01

    Full Text Available OBJETIVO: comparar os resultados neonatais dos partos vaginais espontâneos ou assistidos com fórcipe de Simpson-Braun em nulíparas. MÉTODO: em estudo de corte retrospectivo foram avaliados dois grupos de primíparas atendidas no Centro Obstétrico do CAISM/UNICAMP, que tiveram parto vaginal sob analgesia epidural. O grupo fórcipe foi formado por 119 pacientes que tiveram parto a fórcipe de Simpson-Braun, e o grupo normal por 114 casos de parto vaginal espontâneo. Foram estudadas as variáveis neonatais imediatas como o estado do líquido amniótico e os índices de Apgar, assim como a evolução neonatal nos primeiros dias de vida. Para análise estatística foram utilizados os testes c², exato de Fisher e t de Student para comparação de médias e considerada significativa a diferença correspondente a pPURPOSE: to compare maternal and neonatal outcomes between spontaneous vaginal and Simpson-Braun forceps deliveries in nulliparous women. METHOD: a retrospective study including two groups of nulliparous women, who had vaginal delivery under peridural anesthesia in the obstetric unit of the CAISM-UNICAMP: the forceps group included 119 women who had Simpson-Braun forceps delivery, and the normal group included 114 women who delivered spontaneously. Neonatal outcomes, such as Apgar score and the evolution in the first days of life, were studied. Data were compared in both groups and, for statistical analysis, c² test, Fisher exact, and Student t tests were used. The differences were considered significant when p<0.05. RESULTS: the indications for Simpson-Braun forceps delivery were maternal-fetal relief (90 cases and abbreviation of the expulsive period (29 cases. In the forceps group there were 8 cases (6.7% of vaginal injuries; a similar result was observed in the normal group. The number of hospitalization days for the parturient and the newborns was identical, 2.4 days. The newborns in the two groups had similar Apgar scores

  6. Computational models for analyzing lipoprotein profiles

    NARCIS (Netherlands)

    Graaf, A.A. de; Schalkwijk, D.B. van

    2011-01-01

    At present, several measurement technologies are available for generating highly detailed concentration-size profiles of lipoproteins, offering increased diagnostic potential. Computational models are useful in aiding the interpretation of these complex datasets and making the data more accessible f

  7. Cholesterol in serum lipoprotein fractions after spaceflight

    Science.gov (United States)

    Leach, Carolyn S.; Johnson, Philip C., Jr.; Krauhs, Jane M.; Cintron, Nitza M.

    1988-01-01

    Results are reported from blood-lipid measurements obtained from 125 Space Shuttle crew members before and after space flight. The data are presented in tables and discussed in detail. The main differences noted between preflight and postflight values are a 12.8-percent decrease in high-density lipoproteins on postflight day 1 and significant decreases in total cholesterol and both high- and low-density lipoproteins later in the 23-day postflight period.

  8. Combined analysis of six lipoprotein lipase genetic variants on triglycerides, high-density lipoprotein, and ischemic heart disease

    DEFF Research Database (Denmark)

    Wittrup, Hans H; Andersen, Rolf V; Tybjaerg-Hansen, Anne;

    2006-01-01

    Genetic variants in lipoprotein lipase may affect triglycerides, high-density lipoprotein (HDL), and risk of ischemic heart disease (IHD).......Genetic variants in lipoprotein lipase may affect triglycerides, high-density lipoprotein (HDL), and risk of ischemic heart disease (IHD)....

  9. Genetic determinants of LDL, lipoprotein(a), triglyceride-rich lipoproteins and HDL: concordance and discordance with cardiovascular disease risk

    DEFF Research Database (Denmark)

    Nordestgaard, Børge G; Tybjærg-Hansen, Anne

    2011-01-01

    To evaluate whether new and known genetic determinants of plasma levels of LDL cholesterol, lipoprotein(a), triglyceride-rich lipoproteins, and HDL cholesterol associate with the risk of cardiovascular disease expected from the effect on lipoprotein levels. Concordance or discordance of such gene...... genetic determinants with cardiovascular disease risk will either favor or disfavor that these lipoproteins are causally related to cardiovascular disease.......To evaluate whether new and known genetic determinants of plasma levels of LDL cholesterol, lipoprotein(a), triglyceride-rich lipoproteins, and HDL cholesterol associate with the risk of cardiovascular disease expected from the effect on lipoprotein levels. Concordance or discordance of such...

  10. Engineering support services for the DOE/GRI coal-gasification research program. Addendum to C. F. Braun report FE-2240-46, basic requirements for the design and construction of gasifier vessels

    Energy Technology Data Exchange (ETDEWEB)

    Bostwick, L.E.; Hung, D.T.; Glasgow, P.E.

    1981-04-01

    The C.F. Braun and Co. report FE-2240-46, Basic Requirements for the Design and Construction of Gasifier Vessels, is a well-organized, well-written and comprehensive compendium of information. Kellogg's review of the document disclosed certain areas in which revisions would increase the usefulness of the document to the designer/constructor of gasifier vessels. Rather than rewriting and revising the Braun report, Kellogg proposed, and the DOE/GRI Joint Operating Committee agreed, that an addendum to the report would be of greatest utility. The Kellogg addendum to the C.F. Braun report supplements, amplifies, and updates the Braun information so that the total body of information is compatible with the various codes and practices of vessel design and construction. Paragraph numbers in the Kellogg addendum correspond to the numbers in the Braun report. To avoid confusion, in each of 33 revisions the complete paragraph is included, even though the revision may be the changing of only a few words. Following each such revision is a short comment that outlines the reason for the revision. Kellogg believes that this type of treatment allows side-by-side comparison of the paragraphs and thus results in the greatest utility to the designer/constructor of gasifier vessels.

  11. Pathology and first report of natural infections of the eye trematode Philophthalmus lachrymosus Braun, 1902 (Digenea, Philophthalmidae in a non-human mammalian host

    Directory of Open Access Journals (Sweden)

    Roberto Magalhães Pinto

    2005-10-01

    Full Text Available The avian eye trematode Philophthalmus lachrymosus Braun, 1902 is for the first time referred naturally occurring in a non-human mammalian host. Previously, natural infections with P. lachrymosus and other species of Philophthalmus have been occasionally reported from man, with few data on experimental infections of non-human mammals. Results presented here are related to the report of two cases of philophthalmosis due to natural infections of wild Brazilian capybaras, Hydrochaeris hydrochaeris L., 1766 with P. lachrymosus and associated pathology. Clinical signs, gross and microscopic lesions as well as new morphometric data on the parasite are presented.

  12. Selection of hyperadherent mutants in Pseudomonas putida biofilms

    DEFF Research Database (Denmark)

    Yousef-Coronado, Fatima; Soriano, María Isabel; Yang, Liang;

    2011-01-01

    A number of genetic determinants required for bacterial colonization of solid surfaces and biofilm formation have been identified in different micro-organisms. There are fewer accounts of mutations that favour the transition to a sessile mode of life. Here we report the isolation of random...... transposon Pseudomonas putida KT2440 mutants showing increased biofilm formation, and the detailed characterization of one of them. This mutant exhibits a complex phenotype, including altered colony morphology, increased production of extracellular polymeric substances and enhanced swarming motility, along...... with the formation of denser and more complex biofilms than the parental strain. Sequence analysis revealed that the pleiotropic phenotype exhibited by the mutant resulted from the accumulation of two mutations: a transposon insertion, which disrupted a predicted outer membrane lipoprotein, and a point mutation...

  13. Selective association of outer surface lipoproteins with the lipid rafts of Borrelia burgdorferi.

    Science.gov (United States)

    Toledo, Alvaro; Crowley, Jameson T; Coleman, James L; LaRocca, Timothy J; Chiantia, Salvatore; London, Erwin; Benach, Jorge L

    2014-03-11

    Borrelia burgdorferi contains unique cholesterol-glycolipid-rich lipid rafts that are associated with lipoproteins. These complexes suggest the existence of macromolecular structures that have not been reported for prokaryotes. Outer surface lipoproteins OspA, OspB, and OspC were studied for their participation in the formation of lipid rafts. Single-gene deletion mutants with deletions of ospA, ospB, and ospC and a spontaneous gene mutant, strain B313, which does not express OspA and OspB, were used to establish their structural roles in the lipid rafts. All mutant strains used in this study produced detergent-resistant membranes, a common characteristic of lipid rafts, and had similar lipid and protein slot blot profiles. Lipoproteins OspA and OspB but not OspC were shown to be associated with lipid rafts by transmission electron microscopy. When the ability to form lipid rafts in live B. burgdorferi spirochetes was measured by fluorescence resonance energy transfer (FRET), strain B313 showed a statistically significant lower level of segregation into ordered and disordered membrane domains than did the wild-type and the other single-deletion mutants. The transformation of a B313 strain with a shuttle plasmid containing ospA restored the phenotype shared by the wild type and the single-deletion mutants, demonstrating that OspA and OspB have redundant functions. In contrast, a transformed B313 overexpressing OspC neither rescued the FRET nor colocalized with the lipid rafts. Because these lipoproteins are expressed at different stages of the life cycle of B. burgdorferi, their selective association is likely to have an important role in the structure of prokaryotic lipid rafts and in the organism's adaptation to changing environments. IMPORTANCE Lipid rafts are cholesterol-rich clusters within the membranes of cells. Lipid rafts contain proteins that have functions in sensing the cell environment and transmitting signals. Although selective proteins are present in

  14. Increased transvascular lipoprotein transport in diabetes

    DEFF Research Database (Denmark)

    Jensen, Jan Skov; Feldt-Rasmussen, Bo; Borch-Johnsen, Knut;

    2005-01-01

    likely were not caused by altered hepatic LDL receptor expression, glycosylation of LDL, small LDL size, or medicine use. CONCLUSIONS: Transvascular LDL transport is increased in patients with diabetes mellitus, especially if systolic hypertension or albuminuria is present. Accordingly, lipoprotein flux......CONTEXT: Diabetes is associated with a highly increased risk of atherosclerosis, especially if hypertension or albuminuria is present. OBJECTIVE: We hypothesized that the increased transvascular lipoprotein transport in diabetes may be further accelerated if hypertension or albuminuria is present......, possibly explaining increased intimal lipoprotein accumulation and thus atherosclerosis. DESIGN: The study was cross-sectional and was performed in 1999-2002. SETTING: The study took place in the referral center. PATIENTS: The patients included 60 with diabetes mellitus (27 with type 1 diabetes and 33...

  15. Lipoprotein apheresis for the treatment of elevated circulating levels of lipoprotein(a): a critical literature review

    Science.gov (United States)

    Franchini, Massimo; Capuzzo, Enrico; Liumbruno, Giancarlo M.

    2016-01-01

    Lipoprotein(a), which consists of a low-density lipoprotein (LDL) particle linked to an apolipoprotein(a) moiety, is currently considered an independent risk factor for cardiovascular disease due to its atherogenic (LDL-like) and prothrombotic (plasminogen-like) properties. The aim of this review is to provide an overview of the current and newer therapies for lowering increased lipoprotein(a) levels, focusing on lipoprotein apheresis. After a systematic literature search, we identified ten studies which, overall, documented that lipoprotein apheresis is effective in reducing increased lipoprotein(a) levels and cardiovascular events. PMID:26710351

  16. Analysis of individual lipoproteins and liposomes

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, D.L.; Keller, R.A.; Nolan, J.P. [and others

    1997-08-01

    We describe the application of single molecule detection (SMD) technologies for the analysis of natural (serum lipoproteins) and synthetic (liposomes) transport systems. The need for advanced analytical procedures of these complex and important systems is presented with the specific enhancements afforded by SMD with flowing sample streams. In contrast to bulk measurements which yield only average values, measurement of individual species allows creation of population histograms from heterogeneous samples. The data are acquired in minutes and the analysis requires relatively small sample quantities. Preliminary data are presented from the analysis of low density lipoprotein, and multilamellar and unilamellar vesicles.

  17. Opening and closing of the hydrophobic cavity of LolA coupled to lipoprotein binding and release.

    Science.gov (United States)

    Oguchi, Yuki; Takeda, Kazuki; Watanabe, Shoji; Yokota, Naoko; Miki, Kunio; Tokuda, Hajime

    2008-09-12

    Outer membrane-specific lipoproteins of Escherichia coli are released from the inner membrane through the action of Lol-CDE, which leads to the formation of a complex between the lipoprotein and LolA, a periplasmic chaperone. LolA then transfers lipoproteins to LolB, a receptor in the outer membrane. The structures of LolA and LolB are very similar, having an incomplete beta-barrel covered with an alpha-helical lid forming a hydrophobic cavity inside. The cavity of LolA, but not that of LolB, is closed and thus inaccessible to the bulk solvent. Previous studies suggested that Arg at position 43 of LolA is critical for maintaining this closed structure. We show here, through a crystallographic study, that the cavity of the LolA(R43L) mutant, in which Leu replaces Arg-43, is indeed open to the external milieu. We then found that the binding of a fluorescence probe distinguishes the open/close state of the cavity. Furthermore, it was revealed that the hydrophobic cavity of LolA opens upon the binding of lipoproteins. Such a liganded LolA was found to be inactive in the release of lipoproteins from the inner membrane. On the other hand, the liganded LolA became fully functional when lipoproteins were removed from LolA by detergent treatment or transferred to LolB. Free LolA thus formed was inaccessible to a fluorescence probe. These results, taken together, reveal the LolA cycle, in which the hydrophobic cavity undergoes opening and closing upon the binding and release of lipoproteins, respectively. PMID:18617521

  18. Metabolism of high density lipoproteins in liver cancer

    Institute of Scientific and Technical Information of China (English)

    Jing-Ting Jiang; Ning Xu; Chang-Ping Wu

    2007-01-01

    Liver plays a vital role in the production and catabolism of plasma lipoproteins. It depends on the integrity of cellular function of liver, which ensures homeostasis of lipid and lipoprotein metabolism. When liver cancer occurs these processes are impaired and high-density lipoproteins are changed.

  19. Lipoprotein lipase isoelectric point isoforms in humans

    DEFF Research Database (Denmark)

    Badia-Villanueva, M.; Carulla, P.; Carrascal, M.;

    2014-01-01

    Lipoprotein lipase (LPL) hydrolyzes circulating triacylglycerols (TAG) into free fatty acids and glycerol. It is present in almost all tissues and its tissue-specific regulation directs the flow of circulating TAG in the body. We demonstrated in a previous study that, in rat heart and post...

  20. Effect of apolipoprotein E variants on lipolysis of very low density lipoproteins by heparan sulphate proteoglycan-bound lipoprotein lipase

    NARCIS (Netherlands)

    Man, F.H.A.F. de; Beer, F. de; Laarse, A. van der; Smelt, A.H.M.; Leuven, J.A.G.; Havekes, L.M.

    1998-01-01

    Lipoprotein lipase (LPL) is bound to heparan sulphate proteoglycans (HSPG) at the luminal surface of endothelium. It is the key enzyme involved in the hydrolysis of very low density lipoproteins (VLDL). Prior to lipolysis by LPL, the lipoproteins are considered to interact with vessel wall HSPG. Apo

  1. Genetic determinants of LDL, lipoprotein(a), triglyceride-rich lipoproteins and HDL: concordance and discordance with cardiovascular disease risk

    DEFF Research Database (Denmark)

    Nordestgaard, Børge G; Tybjærg-Hansen, Anne

    2011-01-01

    To evaluate whether new and known genetic determinants of plasma levels of LDL cholesterol, lipoprotein(a), triglyceride-rich lipoproteins, and HDL cholesterol associate with the risk of cardiovascular disease expected from the effect on lipoprotein levels. Concordance or discordance...

  2. Paragonimus y paragonimiasis en el norte peruano. Infección natural de Pseudothelphusa chilensis por metacercarias de Paragonimus Braun, 1899

    Directory of Open Access Journals (Sweden)

    César Cuba

    2014-06-01

    Full Text Available Se ha estudiado el índice de infección natural y la intensidad del parasitismo en cangrejos recolectados en tres provincias del Departamento de Cajamarca, Perú, habiéndose encontrado metacercarias de Paragonimus Braun, 1899 en el 43.97% de 539 especímenes de Pseudothelphusa chilensis Milne Edwards, 1843, único cangrejo hallado en la zona. El órgano parasitado fue casi exclusivamente el hepatopancreas, siendo 10.33 el número promedio de metacercarias por cangrejo. Las formas adultos logradas mediante inoculación de las metacercarias, fueron identificadas como Paragonimus peruvianus Miyazaki, Ibáñez y Miranda, 1969, con excepción de tres ejemplares que correspondieron a lo especie Paragonimus caliensis Little, 1968.

  3. Catalytically inactive lipoprotein lipase expression in muscle of transgenic mice increases very low density lipoprotein uptake: Direct evidence that lipoprotein lipase bridging occurs in vivo

    OpenAIRE

    Merkel, Martin; Kako, Yuko; Radner, Herbert; Cho, Irene S.; Ramasamy, Ravi; Brunzell, John D.; Goldberg, Ira J.; Breslow, Jan L.

    1998-01-01

    Lipoprotein lipase (LPL) is the central enzyme in plasma triglyceride hydrolysis. In vitro studies have shown that LPL also can enhance lipoprotein uptake into cells via pathways that are independent of catalytic activity but require LPL as a molecular bridge between lipoproteins and proteoglycans or receptors. To investigate whether this bridging function occurs in vivo, two transgenic mouse lines were established expressing a muscle creatine kinase promoter-driven human LPL (hLPL) minigene ...

  4. Productive mutants of niger

    International Nuclear Information System (INIS)

    Seeds of six niger (Guizotia abyssinica Cass.) varieties ('GA-10', 'ONS-8', 'IGP-72', 'N-71', 'NB-9' and 'UN-4') were treated with 0.5, 0.75 and 1% ethyl methanesulphonate. After four generations of selection, 29 mutant lines were developed and those were evaluated from 1990-92 during Kharif (July to October) and Rabi (December to March) seasons. Average plant characteristics and yield data of four high yielding mutants along with 'IGP-76' (National Check), GA-10 (Zonal Check) and 'Semiliguda Local' (Local Check) are presented

  5. Release of endothelial cell lipoprotein lipase by plasma lipoproteins and free fatty acids

    International Nuclear Information System (INIS)

    Lipoprotein lipase (LPL) bound to the lumenal surface of vascular endothelial cells is responsible for the hydrolysis of triglycerides in plasma lipoproteins. Studies were performed to investigate whether human plasma lipoproteins and/or free fatty acids would release LPL which was bound to endothelial cells. Purified bovine milk LPL was incubated with cultured porcine aortic endothelial cells resulting in the association of enzyme activity with the cells. When the cells were then incubated with media containing chylomicrons or very low density lipoproteins (VLDL), a concentration-dependent decrease in the cell-associated LPL enzymatic activity was observed. In contrast, incubation with media containing low density lipoproteins or high density lipoproteins produced a much smaller decrease in the cell-associated enzymatic activity. The addition of increasing molar ratios of oleic acid:bovine serum albumin to the media also reduced enzyme activity associated with the endothelial cells. To determine whether the decrease in LPL activity was due to release of the enzyme from the cells or inactivation of the enzyme, studies were performed utilizing radioiodinated bovine LPL. Radiolabeled LPL protein was released from endothelial cells by chylomicrons, VLDL, and by free fatty acids (i.e. oleic acid bound to bovine serum albumin). The release of radiolabeled LPL by VLDL correlated with the generation of free fatty acids from the hydrolysis of VLDL triglyceride by LPL bound to the cells. Inhibition of LPL enzymatic activity by use of a specific monoclonal antibody, reduced the extent of release of 125I-LPL from the endothelial cells by the added VLDL. These results demonstrated that LPL enzymatic activity and protein were removed from endothelial cells by triglyceride-rich lipoproteins (chylomicrons and VLDL) and oleic acid

  6. High density lipoproteins and atherosclerosis: emerging aspects

    Institute of Scientific and Technical Information of China (English)

    Federica Sala; Alberico Luigi Catapano; Giuseppe Danilo Norata

    2012-01-01

    High density lipoproteins (HDL) promote the efflux of excess cholesterol from peripheral tissues to the liver for excretion. This ability is responsible for the most relevant anti-atherogenic effect of HDL. The ability of HDL to promote cholesterol efflux results also in the modulation of a series of responses in the immune cells involved in atherosclerosis, including monocyte-macrophages, B and T lymphocytes.Furthermore, during inflammation, the composition of this class of lipoproteins varies to a large extent, thus promoting the formation of dysfunctional HDL. The aim of this review is to discuss the emerging role of HDL in modulating the activity of immune cells and immune-inflammatory mediators during atherogenesis.

  7. Mycoplasma lipoproteins and Toll-like receptors

    Institute of Scientific and Technical Information of China (English)

    Ling-ling ZUO; Yi-mou WU; Xiao-xing YOU

    2009-01-01

    Mycoplasmas, the smallest free-living, self-replicating bacteria with diameters of 200 to 800 nm, have been reported to be associated with human diseases. It is well known that the mycoplasma lipoprotein/peptide is able to modulate the host immune system, whose N-terminal structure is an important factor in inducing immunity and distinguishing Toll-like receptors (TLRs). However, there is still no clear elucidation about the pathogenic mechanism of mycoplasma lipoprotein/peptide and the signaling pathway. Some researchers have focused on understanding the structures of these proteins and the relationships between their structure and biological function. This review provides an update on the research in this field.

  8. Lipoprotein lipase deficiency with visceral xanthomas

    Energy Technology Data Exchange (ETDEWEB)

    Servaes, Sabah; Bellah, Richard [Department of Radiology, Philadelphia, PA (United States); Verma, Ritu [Department of Gastroenterology, Philadelphia, PA (United States); Pawel, Bruce [Department of Pathology, Philadelphia, PA (United States)

    2010-08-15

    Lipoprotein lipase deficiency (LLD) is a rare metabolic disorder that typically presents with skin xanthomas and pancreatitis in childhood. We report a case of LLD in an infant who presented with jaundice caused by a pancreatic head mass. Abdominal imaging also incidentally revealed hyperechoic renal masses caused by renal xanthomas. This appearance of the multiple abdominal masses makes this a unique infantile presentation of LLD. (orig.)

  9. New targets and developments in lipoproteins control

    Directory of Open Access Journals (Sweden)

    Norata GD

    2013-05-01

    Full Text Available Giuseppe Danilo Norata1–31Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Italy; 2Center for the Study of Atherosclerosis, Società Italiana Studio Aterosclerosi, Ospedale Bassini, Cinisello Balsamo, Italy; 3The Blizard Institute, Centre for Diabetes, Barts and The London School of Medicine and Dentistry, Queen Mary University, London, UKAbstract: Statins provide a very effective approach in reducing plasma cholesterol levels and cardiovascular risk. However, the proportion of patients who fail to achieve desirable plasma lipid levels ranges from 16%–53%, worldwide. This percentage reaches up to 80% in patients with familial hypercholesterolemia. Additionally, many patients are unable to tolerate statins, particularly at the highest approved dose level. New treatments that aggressively reduce lipid levels in patients with severe hypercholesterolemia, or those unable to reach their lipid targets, are therefore required. The most promising approaches in this context, such as inhibitors of the synthesis of apolipoprotein B (apoB containing lipoproteins (apoB silencing or microsomal triglyceride transfer protein [MTP] inhibition or proprotein convertase subtilisin/kexin type 9 (PCSK9 blockers, all decrease low-density lipoprotein (LDL extensively. Increasing low levels of high-density lipoprotein (HDL cholesterol via cholesteryl ester transfer protein inhibitors or apolipoprotein A-1 (ApoA-1 inducers and improving their quality with HDL or ApoA-1 mimetics represent also important options. Drugs affecting HDL, however, may not be all alike and require adequate scrutiny of the mechanisms involved. Until we have a better understanding of these issues, further LDL lowering in high-risk patients represents the soundest approach.Keywords: apolipoproteins, lipids, lipoprotein classes, hypercholesterolemia, synthesis, LDL lowering

  10. Sortilins: new players in lipoprotein metabolism

    DEFF Research Database (Denmark)

    Willnow, Thomas; Kjølby, Mads Fuglsang; Nykjær, Anders

    2011-01-01

    PURPOSE OF REVIEW: Sortilins are sorting receptors that direct proteins through secretory and endocytic pathways of the cell. Previously, these receptors have been shown to play important roles in regulating protein transport in neurons and to control neuronal viability and death in many diseases...... on the importance of sorting receptors in control of cellular and systemic lipoprotein metabolism and how altered trafficking pathways may represent a major risk factor for dyslipidemia and atherosclerosis in the human population....

  11. Abnormal high density lipoproteins in cerebrotendinous xanthomatosis

    Energy Technology Data Exchange (ETDEWEB)

    Shore, V. (Lawrence Livermore Lab., CA); Salen, G.; Cheng, F.W.; Forte, T.; Shefer, S.; Tint, G.S.

    1981-11-01

    The plasma lipoprotein profiles and high density lipoproteins (HDL) were characterized in patients with the genetic disease cerebrotendinous xanthomatosis (CTX). The mean HDL-cholesterol concentration in the CTX plasmas was 14.5 +/- 3.2 mg/dl, about one-third the normal value. The low HDL-cholesterol reflects a low concentration and an abnormal lipid composition of the plasma HDL. Relative to normal HDL, the cholesteryl esters are low, free cholesterol and phospholipids essentially normal, and triglycerides increased. The ratio of apoprotein (apo) to total cholesterol in the HDL of CTX was two to three times greater than normal. In the CTX HDL, the ratio of apoAI to apoAII was high, the proportion of apoC low, and a normally minor form of apoAI increased relative to other forms. The HDL in electron micrographs appeared normal morphologically and in particle size. The adnormalities in lipoprotein distribution profiles and composition of the plasma HDL result from metabolic defects that are not understood but may be linked to the genetic defect in bile acid synthesis in CTX. As a consequence, it is probable that the normal functions of the HDL, possibly including modulation of LDL-cholesterol uptake and the removal of excess cholesterol from peripheral tissues, are perturbed significantly in this disease.

  12. Lipoprotein biosynthesis as a target for anti-Wolbachia treatment of filarial nematodes

    Directory of Open Access Journals (Sweden)

    Slatko Barton E

    2010-10-01

    Full Text Available Abstract Background Lymphatic filariasis and onchocerciasis are debilitating diseases caused by filarial nematodes. Disease pathogenesis is induced by inflammatory responses following the death of the parasite. Wolbachia endosymbionts of filariae are potent inducers of innate and adaptive inflammation and bacterial lipoproteins have been identified as the ligands that bind toll-like receptors (TLR 2 and TLR6. Lipoproteins are important structural and functional components of bacteria and therefore enzymes involved in Wolbachia lipoprotein biosynthesis are potential chemotherapeutic targets. Results Globomycin, a signal peptidase II (LspA inhibitor, has activity against Gram-negative bacteria and a putative lspA gene has been identified from the Wolbachia genome of Brugia malayi (wBm. The amino acids required for function are strictly conserved and functionality was verified by complementation tests in a temperature-sensitive Escherichia coli lspA mutant. Also, transformation of wild type E. coli with Wolbachia lspA conferred significant globomycin resistance. A cell-based screen has been developed utilizing a Wolbachia-containing Aedes albopictus cell line to assay novel compounds active against Wolbachia. Globomycin was screened using this assay, which resulted in a dose-dependent reduction in Wolbachia load. Furthermore, globomycin was also effective in reducing the motility and viability of adult B. malayi in vitro. Conclusions These studies validate lipoprotein biosynthesis as a target in an organism for which no genetic tools are available. Further studies to evaluate drugs targeting this pathway are underway as part of the A-WOL drug discovery and development program.

  13. MCP-1 binds to oxidized LDL and is carried by lipoprotein(a) in human plasma

    Science.gov (United States)

    Wiesner, Philipp; Tafelmeier, Maria; Chittka, Dominik; Choi, Soo-Ho; Zhang, Li; Byun, Young Sup; Almazan, Felicidad; Yang, Xiaohong; Iqbal, Navaid; Chowdhury, Punam; Maisel, Alan; Witztum, Joseph L.; Handel, Tracy M.; Tsimikas, Sotirios; Miller, Yury I.

    2013-01-01

    Lipoprotein oxidation plays an important role in pathogenesis of atherosclerosis. Oxidized low density lipoprotein (OxLDL) induces profound inflammatory responses in vascular cells, such as production of monocyte chemoattractant protein-1 (MCP-1) [chemokine (C-C motif) ligand 2], a key chemokine in the initiation and progression of vascular inflammation. Here we demonstrate that OxLDL also binds MCP-1 and that the OxLDL-bound MCP-1 retains its ability to recruit monocytes. A human MCP-1 mutant in which basic amino acids Arg-18 and Lys-19 were replaced with Ala did not bind to OxLDL. The MCP-1 binding to OxLDL was inhibited by the monoclonal antibody E06, which binds oxidized phospholipids (OxPLs) in OxLDL. Because OxPLs are carried by lipoprotein(a) [Lp(a)] in human plasma, we tested to determine whether Lp(a) binds MCP-1. Recombinant wild-type but not mutant MCP-1 added to human plasma bound to Lp(a), and its binding was inhibited by E06. Lp(a) captured from human plasma contained MCP-1 and the Lp(a)-associated endogenous MCP-1 induced monocyte migration. These results demonstrate that OxLDL and Lp(a) bind MCP-1 in vitro and in vivo and that OxPLs are major determinants of the MCP-1 binding. The association of MCP-1 with OxLDL and Lp(a) may play a role in modulating monocyte trafficking during atherogenesis. PMID:23667177

  14. Lipoprotein-induced phenoloxidase-activity in tarantula hemocyanin.

    Science.gov (United States)

    Schenk, Sven; Schmidt, Juliane; Hoeger, Ulrich; Decker, Heinz

    2015-08-01

    Phenoloxidases play vital roles in invertebrate innate immune reactions, wound closure and sclerotization processes in arthropods. In chelicerates, where phenoloxidases are lacking, phenoloxidase-activity can be induced in the oxygen carrier hemocyanin in vitro by proteolytic cleavage, incubation with the artificial inducer SDS, or lipids. The role of protein-protein interaction has up to now received little attention. This is remarkable, as lipoproteins - complexes of proteins and lipids - are present at high concentrations in arthropod hemolymph. We characterized the three lipoproteins present in tarantula hemolymph, two high-density lipoproteins and one very high-density lipoprotein, and show that the two high-density lipoproteins have distinct structures: the more abundant high-density lipoprotein is an ellipsoid particle with axes of ~22.5 nm and ~16.8 nm, respectively. The second high-density lipoprotein, present only in trace amount, is a large discoidal lipoprotein with a diameter of ~38.4 nm and an on-edge thickness of ~7.1 nm. We further demonstrate that the interaction between lipoproteins and hemocyanin induces phenoloxidase activity in hemocyanin, and propose that this activation is due to protein-protein interaction rather than protein-lipid interaction, as neither lipid micelles nor lipid monomers were found to be activating. Activation was strongest in the presence of high-density lipoproteins; very high-density lipoproteins were found to be non-activating. This is the first time that the ability of lipoproteins to induce phenoloxidase activity of hemocyanin has been demonstrated, thus adding novel aspects to the function of lipoproteins apart from their known role in nutrient supply. PMID:25817204

  15. Treatment of hypothyroidism reduces low-density lipoproteins but not lipoprotein(a)

    DEFF Research Database (Denmark)

    Klausen, I C; Nielsen, F E; Hegedüs, L;

    1992-01-01

    Lipoprotein(a) [Lp(a)] is a low-density lipoprotein (LDL) particle in which apolipoprotein B-100 (apo B) is attached to a large plasminogen-like protein called apolipoprotein(a) [apo(a)]. Apo(a) has several genetically determined phenotypes differing in molecular weight, to which Lp(a) concentrat......, which is a ligand for the LDL receptor, it is surprising that Lp(a) is not reduced along with LDL and apo B. These findings suggest that the catabolism of LDL and Lp(a) differ in some respect, and that thyroid hormones have little, if any, effect on Lp(a)....

  16. Human placenta secretes apolipoprotein B-100-containing lipoproteins

    DEFF Research Database (Denmark)

    Munk-Madsen, Eva; Lindegaard, Marie Louise Skakkebæk; Andersen, Claus B;

    2004-01-01

    early during pregnancy in the placenta. To examine whether the human placenta produces lipoproteins, we examined apoB and microsomal triglyceride transfer protein (MTP) mRNA expression in placental biopsies. ApoB and MTP are mandatory for assembly and secretion of apoB-containing lipoproteins. Both...... genes were expressed in placenta and microsomal extracts from human placenta contained triglyceride transfer activity, indicating expression of bioactive MTP. To detect lipoprotein secretion, biopsies from term placentas were placed in medium with [(35)S]methionine and [(35)S]cysteine for 3-24 h. Upon...... lipoproteins secreted from placental tissue showed spherical particles with a diameter of 47 +/- 10 nm. These results demonstrate that human placenta expresses both apoB and MTP and consequently synthesize and secrete apoB-100-containing lipoproteins. Placental lipoprotein formation constitutes a novel pathway...

  17. Regulation of Lipoprotein(a) by interleukin-6 in humans

    OpenAIRE

    Müller, Nike

    2014-01-01

    Cardiovascular disease is still the leading cause of death in the western world in men and women. There are several factors such as visceral obesity, hypertension, insulin resistance and atherogenic dyslipidemia which substantially contribute to a risk of cardiovascular death. Low-density lipoprotein (LDL) molecules initiate early atherogenesis. One of the most atherogenic lipoproteins is lipoprotein(a) [Lp(a)], which consists of a LDL-like particle and apolipoprotein(a) [apo(a)]. However, ci...

  18. Comparison of Carbohydrate Compositions of Total Apolipoproteins in Lipoproteins

    OpenAIRE

    Güldür, Tayfun; OZAN, Sema; İLERİ, Tülay

    1998-01-01

    Terminal carbohydrate moieties of apolipoproteins of lipoproteins in human and goat serum were ascertained and compared. Apolipoproteins of b+pre-b (apolipoprotein B containing lipoproteins) and a lipoproteins separated by phosphotungstic acid/MgCl2 precipitation method were applied to SDS-PAGE and blotted onto nitrocellulose membrane. Digoxigenin labelled lectins, each of which recognizes a specific sugar sequence, were incubated with apolipoproteins immobilized on a western blot membrane to...

  19. Outer membrane lipoprotein biogenesis: Lol is not the end.

    Science.gov (United States)

    Konovalova, Anna; Silhavy, Thomas J

    2015-10-01

    Bacterial lipoproteins are lipid-anchored proteins that contain acyl groups covalently attached to the N-terminal cysteine residue of the mature protein. Lipoproteins are synthesized in precursor form with an N-terminal signal sequence (SS) that targets translocation across the cytoplasmic or inner membrane (IM). Lipid modification and SS processing take place at the periplasmic face of the IM. Outer membrane (OM) lipoproteins take the localization of lipoproteins (Lol) export pathway, which ends with the insertion of the N-terminal lipid moiety into the inner leaflet of the OM. For many lipoproteins, the biogenesis pathway ends here. We provide examples of lipoproteins that adopt complex topologies in the OM that include transmembrane and surface-exposed domains. Biogenesis of such lipoproteins requires additional steps beyond the Lol pathway. In at least one case, lipoprotein sequences reach the cell surface by being threaded through the lumen of a beta-barrel protein in an assembly reaction that requires the heteropentomeric Bam complex. The inability to predict surface exposure reinforces the importance of experimental verification of lipoprotein topology and we will discuss some of the methods used to study OM protein topology. PMID:26370942

  20. The effect of bafilomycin A1 and protease inhibitors on the degradation and recycling of a Class 5-mutant LDLR

    Institute of Scientific and Technical Information of China (English)

    Kristian Tveten; Trine Ranheim; Knut Erik Berge; Trond P.Leren; Mari Ann Kulseth

    2009-01-01

    The low-density lipoprotein receptor (LDLR) mediates cholesterol homeostasis through endocytosis of lipoprotein particles, particularly low-density lipoproteins (LDLs). Normally, the lipoprotein particles are released in the endosomes and the receptors recycle to the cell surface. Familial hypercholesterolemia (FH) is an autoso-mal dominant disease caused by mutations in the gene encoding the LDLR. These mutations are divided into five functional classes where Class 5 mutations encode receptors that suffer from ligand-induced degradation and recycling deficiency. The aim of this study was to investigate whether it is possible to prevent the fast ligand-induced degradation of Class 5-mutant LDLR and to restore its ability to recycle to the cell surface. E387K is a naturally occurring Class 5 mutation found in FH patients, and in the present study, we used Chinese hamster ovary cells transfected with an E387K-mutant LDLR. Abrogation of endosomal acidification by adding bafilomycin Al or addition of the irreversible serine protease inhibitors, 4-(2-aminoethyl)-benzenesulfonyl fluoride (AEBSF) and 3,4-dichloroisocoumarin (DCI), prevented the degradation of the E387K-mutant LDLR. However, the undegraded receptor did not recycle to the cell surface in the presence of LDL. Unexpectedly, AEBSF caused aggregation of early endosome antigen-1-positive endosomes and the intracellular trapped LDLR co-localized with these aggregated early endosomes.

  1. Homology of lipoprotein lipase to pancreatic lipase.

    OpenAIRE

    Ben-Avram, C M; Ben-Zeev, O; Lee, T.D. (Taunia D.); Haaga, K; Shively, J. E.; Goers, J; Pedersen, M.E; Reeve, J R; Schotz, M C

    1986-01-01

    Bovine milk lipoprotein lipase was subjected to amino acid sequence analysis. The first 19 amino-terminal residues were Asp-Arg-Ile-Thr-Gly-Gly-Lys-Asp-Phe-Arg-Asp-Ile-Glu-Ser-Lys-Phe-Ala-Leu- Arg. In addition, reversed-phase high-performance liquid chromatography of a tryptic digest of reduced and alkylated lipase resolved a number of peptides, five of which contained cysteine. Sequence analysis of the tryptic peptides revealed in most instances a close homology to porcine pancreatic lipase....

  2. DMPD: Lipoprotein trafficking in vascular cells. Molecular Trojan horses and cellularsaboteurs. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 9287290 Lipoprotein trafficking in vascular cells. Molecular Trojan horses and cell...ml) Show Lipoprotein trafficking in vascular cells. Molecular Trojan horses and cellularsaboteurs. PubmedID ...9287290 Title Lipoprotein trafficking in vascular cells. Molecular Trojan horses

  3. Lipoproteins, cholesterol homeostasis and cardiac health

    Directory of Open Access Journals (Sweden)

    Tyler F. Daniels, Karen M. Killinger, Jennifer J. Michal, Raymond W. Wright Jr., Zhihua Jiang

    2009-01-01

    Full Text Available Cholesterol is an essential substance involved in many functions, such as maintaining cell membranes, manufacturing vitamin D on surface of the skin, producing hormones, and possibly helping cell connections in the brain. When cholesterol levels rise in the blood, they can, however, have dangerous consequences. In particular, cholesterol has generated considerable notoriety for its causative role in atherosclerosis, the leading cause of death in developed countries around the world. Homeostasis of cholesterol is centered on the metabolism of lipoproteins, which mediate transport of the lipid to and from tissues. As a synopsis of the major events and proteins that manage lipoprotein homeostasis, this review contributes to the substantial attention that has recently been directed to this area. Despite intense scrutiny, the majority of phenotypic variation in total cholesterol and related traits eludes explanation by current genetic knowledge. This is somewhat disappointing considering heritability estimates have established these traits as highly genetic. Thus, the continued search for candidate genes, mutations, and mechanisms is vital to our understanding of heart disease at the molecular level. Furthermore, as marker development continues to predict risk of vascular illness, this knowledge has the potential to revolutionize treatment of this leading human disease.

  4. Structure of the human lipoprotein lipase gene

    International Nuclear Information System (INIS)

    Human genomic clones that span the entire lipoprotein lipase (LPL) gene have been isolated and used to determine its structure. The gene is approximately 30 kilobase (kb) pairs in length in which the mRNA specifying sequence is divided into 10 exons. Exons 1-9 are of average size (105-276 bp) whereas exon 10, which specifies the entire 3' uncoding sequence, is 1,948 bp in length. Exon 1 codes for the signal peptide, exon 2 includes the protein domain that was shown to bind to the lipoprotein substrate, and exons 6 and 9 code for sequences that are relatively rich in basic amino acids and therefore likely to be involved in anchoring of the enzyme to the capillary endothelium by interaction with the acidic domain of heparan sulfate. Four closely spaced mRNA 5' termini were observed, indicating multiple transcription initiation sites, one of which seems to be favored. Two potential enhancer sequence motifs in the 5' upstream region were observed. One may specify expression in response to intracellular Ca2+ mobilization, and the other may be responsible for expression in adipocytes

  5. [Atherogenic modification of low-density lipoproteins].

    Science.gov (United States)

    Sukhorukov, V N; Karagodin, V P; Orekhov, A N

    2016-05-01

    One of the first manifestations of atherosclerosis is accumulation of extra- and intracellular cholesterol esters in the arterial intima. Formation of foam cells is considered as a trigger in the pathogenesis of atherosclerosis. Low density lipoprotein (LDL) circulating in human blood is the source of lipids accumulated in the arterial walls. This review considered features and role in atherogenesis different modified forms of LDL: oxidized, small dense, electronegative and especially desialylated LDL. Desialylated LDL of human blood plasma is capable to induce lipid accumulation in cultured cells and it is atherogenic. LDL possesses numerous alterations of protein, carbohydrate and lipid moieties and therefore can be termed multiple-modified LDL. Multiple modification of LDL occurs in human blood plasma and represents a cascade of successive changes in the lipoprotein particle: desialylation, loss of lipids, reduction in the particle size, increase of surface electronegative charge, etc. In addition to intracellular lipid accumulation, stimulatory effects of naturally occurring multiple-modified LDL on other processes involved in the development of atherosclerotic lesions, namely cell proliferation and fibrosis, were shown. PMID:27562992

  6. Turkish Heart Study: lipids, lipoproteins, and apolipoproteins.

    Science.gov (United States)

    Mahley, R W; Palaoğlu, K E; Atak, Z; Dawson-Pepin, J; Langlois, A M; Cheung, V; Onat, H; Fulks, P; Mahley, L L; Vakar, F

    1995-04-01

    We examined the plasma lipids, lipoproteins, and selected apolipoproteins in approximately 9,000 men and women from six different regions of Turkey with markedly different diets, ranging from an Aegean coast diet high in olive oil (plasma cholesteryl ester fatty acids enriched in monounsaturated fatty acids) to an inland Anatolian diet high in meat and dairy products (plasma cholesteryl esters enriched in saturated fatty acids). The rural population consuming an olive oil-rich diet had the lowest plasma cholesterol levels (men, 149 mg/dl; women, 150 mg/dl). The urban populations of Istanbul and Adana had higher plasma cholesterol levels (men, 202 and 184 mg/dl, respectively; women, 181 and 190 mg/dl, respectively). Affluent men had the highest cholesterol levels (207 mg/dl). The low density lipoprotein (LDL) cholesterol levels tended to parallel the total cholesterol levels (highest for Istanbul men at 136 mg/dl and lowest for Aegean coast men and women at approximately 100 mg/dl). Strikingly, the Turkish people were found to have very low levels of high density lipoprotein (HDL) cholesterol (HDL-C) (mean values for all six regions: men, 34-38 mg/dl; women, 37-45 mg/dl) and total cholesterol/HDL-C ratios that were high (mean values for all six regions: men, 4.5-5.5; women, 3.9-5.0). The low HDL-C levels appear to be caused, at least in part, by a genetic factor. Triglyceride levels also tended to be high in Turkish men (approximately 120-150 mg/dl) and women (approximately 90-110 mg/dl). Thus, even though the total plasma cholesterol levels are not excessively elevated in comparison to those in other populations, the presence of low HDL-C or low HDL-C coupled with mildly elevated triglyceride levels may represent a significant risk factor for heart disease in the Turkish population. Affluence and higher education were associated with higher cholesterol levels. Lack of physical activity, smoking, and alcohol consumption also tended to be associated with a

  7. Comparative study of the oospore morphology of two populations of a rare species Chara baueri A. Braun in Cedynia (Poland and Batzlow (Germany

    Directory of Open Access Journals (Sweden)

    Andrzej Pukacz

    2012-06-01

    Full Text Available Morphological features of oospores of Chara baueri A. Braun, one of the rarest charophyte species worldwide, were studied based on 100 oospores collected from a small and temporarily dried mid-field pond near Cedynia, Western Poland. This is the first Polish and fifth presently known locality of this species. For comparison 67 oospores from a German population (similar pond localized near Batzlow, Germany were also measured. So far, data on morphology of C. baueri oospores as well as the species ecology are limited. The only more detailed study of oospores for this species was earlier performed on 15 oospores from Kazakhstan. Largest polar axis (LPA, length, largest equatorial diameter (LED, width, isopolarity index (ISI = LPA/LED × 100, number of ridges, width of fossa, distance from apical pole to LED (AND and anisipolarity index (ANI = AND/LPA × 100 were measured. The comparative analysis revealed that the oospores from Poland are generally bigger and more prolate than the Ger­man ones. The differences for most of studied parameters were statistically significant. The finding is discussed in the context of habitat differentiation of both studied sites. Moreover, the results obtained of oospore measurements for both populations differs from most of the data known so far from the literature.

  8. Alterations of serum cholesterol and serum lipoprotein in breast cancer of women

    OpenAIRE

    Hasija, Kiran; Bagga, Hardeep K.

    2005-01-01

    Fasting blood sample of 50 normal subjects (control) and 100 patients of breast cancer were investigated for serum total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, very low density lipoprotein, high density lipoprotein cholesterol:low density lipoprotein cholesterol ratio and total cholesterol:high density lipoprotein cholesterol ratio during breast cancer of women. Five cancer stages, types, age groups, parity and menopausal status were undertaken...

  9. Mendelian Disorders of High-Density Lipoprotein Metabolism

    NARCIS (Netherlands)

    Oldoni, Federico; Sinke, Richard J.; Kuivenhoven, Jan Albert

    2014-01-01

    High-density lipoproteins (HDLs) are a highly heterogeneous and dynamic group of the smallest and densest lipoproteins present in the circulation. This review provides the current molecular insight into HDL metabolism led by articles describing mutations in genes that have a large affect on HDL chol

  10. TRIIODOTHYRONINE RAPIDLY LOWERS PLASMA-LIPOPROTEIN (A) IN HYPOTHYROID SUBJECTS

    NARCIS (Netherlands)

    DULLAART, RPF; VANDOORMAAL, JJ; HOOGENBERG, K; SLUITER, WJ

    1995-01-01

    Background: Increases in plasma low-density-lipoprotein (LDL) cholesterol and apolipoprotein B (apo-B) are well known in primary hypothyroidism, but it is uncertain whether thyroid dysfunction is associated with elevated levels of the atherogenic lipoprotein (a) (Lp(a)). Methods: The effect of short

  11. The fibrate drug gemfibrozil disrupts lipoprotein metabolism in rainbow trout

    International Nuclear Information System (INIS)

    Gemfibrozil (GEM) is a fibrate drug consistently found in effluents from sewage treatment plants. This study characterizes the pharmacological effects of GEM on the plasma lipoproteins of rainbow trout (Oncorhynchus mykiss). Our goals were to quantify the impact of the drug on: 1) lipid constituents of lipoproteins (phospholipids (PL), triacylglycerol (TAG), and cholesterol), 2) lipoprotein classes (high, low and very low density lipoproteins), and 3) fatty acid composition of lipoproteins. Potential mechanisms of GEM action were investigated by measuring lipoprotein lipase activity (LPL) and the hepatic gene expression of LPL and of the peroxisome proliferator-activated receptor (PPAR) α, β, and γ isoforms. GEM treatment resulted in decreased plasma lipoprotein levels (- 29%) and a reduced size of all lipoprotein classes (lower PL:TAG ratios). However, the increase in HDL-cholesterol elicited by GEM in humans failed to be observed in trout. Therefore, HDL-cholesterol cannot be used to assess the impact of the drug on fish. GEM also modified lipoprotein composition by reducing the abundance of long-chain n-3 fatty acids, thereby potentially reducing the nutritional quality of exposed fish. The relative gene expression of LPL was increased, but the activity of the enzyme was not, and we found no evidence for the activation of PPAR pathways. The depressing effects of GEM on fish lipoproteins demonstrated here may be a concern in view of the widespread presence of fibrates in aquatic environments. Work is needed to test whether exposure to environmental concentrations of these drugs jeopardizes the capacity of fish for reproduction, temperature acclimation or migratory behaviors.

  12. Modulation of low-density lipoprotein-induced inhibition of intercellular communication by antioxidants and high-density lipoproteins

    NARCIS (Netherlands)

    Zwijsen, R M; de Haan, L H; Kuivenhoven, J A; Nusselder, I C

    1991-01-01

    In order to study the capacity of antioxidants and high-density lipoproteins (HDL) to modulate the effects of low-density lipoprotein (LDL) on intercellular communication, arterial smooth muscle cells and a dye transfer method were used. LDL, in contrast to HDL, inhibited the communication between a

  13. Apoc2 loss-of-function zebrafish mutant as a genetic model of hyperlipidemia

    Directory of Open Access Journals (Sweden)

    Chao Liu

    2015-08-01

    Full Text Available Apolipoprotein C-II (APOC2 is an obligatory activator of lipoprotein lipase. Human patients with APOC2 deficiency display severe hypertriglyceridemia while consuming a normal diet, often manifesting xanthomas, lipemia retinalis and pancreatitis. Hypertriglyceridemia is also an important risk factor for development of cardiovascular disease. Animal models to study hypertriglyceridemia are limited, with no Apoc2-knockout mouse reported. To develop a genetic model of hypertriglyceridemia, we generated an apoc2 mutant zebrafish characterized by the loss of Apoc2 function. apoc2 mutants show decreased plasma lipase activity and display chylomicronemia and severe hypertriglyceridemia, which closely resemble the phenotype observed in human patients with APOC2 deficiency. The hypertriglyceridemia in apoc2 mutants is rescued by injection of plasma from wild-type zebrafish or by injection of a human APOC2 mimetic peptide. Consistent with a previous report of a transient apoc2 knockdown, apoc2 mutant larvae have a minor delay in yolk consumption and angiogenesis. Furthermore, apoc2 mutants fed a normal diet accumulate lipid and lipid-laden macrophages in the vasculature, which resemble early events in the development of human atherosclerotic lesions. In addition, apoc2 mutant embryos show ectopic overgrowth of pancreas. Taken together, our data suggest that the apoc2 mutant zebrafish is a robust and versatile animal model to study hypertriglyceridemia and the mechanisms involved in the pathogenesis of associated human diseases.

  14. Lipoprotein particle distribution and skeletal muscle lipoprotein lipase activity after acute exercise

    Directory of Open Access Journals (Sweden)

    Harrison Michael

    2012-07-01

    Full Text Available Abstract Background Many of the metabolic effects of exercise are due to the most recent exercise session. With recent advances in nuclear magnetic resonance spectroscopy (NMRS, it is possible to gain insight about which lipoprotein particles are responsible for mediating exercise effects. Methods Using a randomized cross-over design, very low density lipoprotein (VLDL responses were evaluated in eight men on the morning after i an inactive control trial (CON, ii exercising vigorously on the prior evening for 100 min followed by fasting overnight to maintain an energy and carbohydrate deficit (EX-DEF, and iii after the same exercise session followed by carbohydrate intake to restore muscle glycogen and carbohydrate balance (EX-BAL. Results The intermediate, low and high density lipoprotein particle concentrations did not differ between trials. Fasting triglyceride (TG determined biochemically, and mean VLDL size were lower in EX-DEF but not in EX-BAL compared to CON, primarily due to a reduction in VLDL-TG in the 70–120 nm (large particle range. In contrast, VLDL-TG was lower in both EX-DEF and EX-BAL compared to CON in the 43–55 nm (medium particle range. VLDL-TG in smaller particles (29–43 nm was unaffected by exercise. Because the majority of VLDL particles were in this smallest size range and resistant to change, total VLDL particle concentration was not different between any of these conditions. Skeletal muscle lipoprotein lipase (LPL activity was also not different across these 3 trials. However, in CON only, the inter-individual differences in LPL activity were inversely correlated with fasting TG, VLDL-TG, total, large and small VLDL particle concentration and VLDL size, indicating a regulatory role for LPL in the non-exercised state. Conclusions These findings reveal a high level of differential regulation between different sized triglyceride-rich lipoproteins following exercise and feeding, in the absence of changes in

  15. Lipoprotein particle distribution and skeletal muscle lipoprotein lipase activity after acute exercise

    LENUS (Irish Health Repository)

    Harrison, Michael

    2012-06-06

    AbstractBackgroundMany of the metabolic effects of exercise are due to the most recent exercise session. With recent advances in nuclear magnetic resonance spectroscopy (NMRS), it is possible to gain insight about which lipoprotein particles are responsible for mediating exercise effects.MethodsUsing a randomized cross-over design, very low density lipoprotein (VLDL) responses were evaluated in eight men on the morning after i) an inactive control trial (CON), ii) exercising vigorously on the prior evening for 100 min followed by fasting overnight to maintain an energy and carbohydrate deficit (EX-DEF), and iii) after the same exercise session followed by carbohydrate intake to restore muscle glycogen and carbohydrate balance (EX-BAL).ResultsThe intermediate, low and high density lipoprotein particle concentrations did not differ between trials. Fasting triglyceride (TG) determined biochemically, and mean VLDL size were lower in EX-DEF but not in EX-BAL compared to CON, primarily due to a reduction in VLDL-TG in the 70–120 nm (large) particle range. In contrast, VLDL-TG was lower in both EX-DEF and EX-BAL compared to CON in the 43–55 nm (medium) particle range. VLDL-TG in smaller particles (29–43 nm) was unaffected by exercise. Because the majority of VLDL particles were in this smallest size range and resistant to change, total VLDL particle concentration was not different between any of these conditions. Skeletal muscle lipoprotein lipase (LPL) activity was also not different across these 3 trials. However, in CON only, the inter-individual differences in LPL activity were inversely correlated with fasting TG, VLDL-TG, total, large and small VLDL particle concentration and VLDL size, indicating a regulatory role for LPL in the non-exercised state.ConclusionsThese findings reveal a high level of differential regulation between different sized triglyceride-rich lipoproteins following exercise and feeding, in the absence of changes in LPL activity.

  16. Human placenta secretes apolipoprotein B-100-containing lipoproteins

    DEFF Research Database (Denmark)

    Munk-Madsen, Eva; Lindegaard, Marie Louise Skakkebæk; Andersen, Claus B;

    2004-01-01

    early during pregnancy in the placenta. To examine whether the human placenta produces lipoproteins, we examined apoB and microsomal triglyceride transfer protein (MTP) mRNA expression in placental biopsies. ApoB and MTP are mandatory for assembly and secretion of apoB-containing lipoproteins. Both...... genes were expressed in placenta and microsomal extracts from human placenta contained triglyceride transfer activity, indicating expression of bioactive MTP. To detect lipoprotein secretion, biopsies from term placentas were placed in medium with [(35)S]methionine and [(35)S]cysteine for 3-24 h. Upon...... of lipid transfer from the mother to the developing fetus....

  17. ToxR regulates the production of lipoproteins and the expression of serum resistance in Vibrio cholerae

    International Nuclear Information System (INIS)

    The genes encoding three lipoproteins of Vibrio cholerae were identified by a combination of DNA sequence analysis and [3H]palmitate labeling of hybrid proteins encoded by TnphoA gene fusions. The expression of these three lipoproteins, TagA, AcfD, and TcpC, was controlled by ToxR, the cholera toxin transcriptional activator. The involvement of other bacterial lipoproteins in conferring resistance ot the bactericidal effects of complement prompted us to examine this possibility in V. cholerae. Remarkably, mutations in toxR and tcp genes (including tcpC), involved in the biogenesis of the toxin coregulated pili, rendered V. cholerae about 104 - 106 times more sensitive to the vibriocidal activity of antibody and complement. Since V. cholerae is a noninvasive organism and toxR and tcp mutants are highly defective in intestinal colonization in animals and humans, these results raise the possibility that resistance to a gut-associated, complement-like bactericidal activity may be a major virulence determinant of V. cholerae and other enterobacterial species

  18. Could Lipoprotein Lipase Play a Role in Alzheimer's Disease?

    Directory of Open Access Journals (Sweden)

    Jean-Francois Blain

    2004-01-01

    Full Text Available This paper reviews recent literature on the role of lipoprotein lipase in the central nervous system with a focus on its recently described role in synaptic remodeling. This novel role could have implication for Alzheimer's disease treatment.

  19. Lipid droplet pattern and nondroplet-like structure in two fat mutants of Caenorhabditis elegans revealed by coherent anti-Stokes Raman scattering microscopy

    Science.gov (United States)

    Yi, Yung-Hsiang; Chien, Cheng-Hao; Chen, Wei-Wen; Ma, Tian-Hsiang; Liu, Kuan-Yu; Chang, Yu-Sun; Chang, Ta-Chau; Lo, Szecheng J.

    2014-01-01

    Lipid is an important energy source and essential component for plasma and organelle membranes in all kinds of cells. Coherent anti-Stokes Raman scattering (CARS) microscopy is a label-free and nonlinear optical technique that can be used to monitor the lipid distribution in live organisms. Here, we utilize CARS microscopy to investigate the pattern of lipid droplets in two live Caenorhabditis elegans mutants (fat-2 and fat-3). The CARS images showed a striking decrease in the size, number, and content of lipid droplets in the fat-2 mutant but a slight difference in the fat-3 mutant as compared with the wild-type worm. Moreover, a nondroplet-like structure with enhanced CARS signal was detected for the first time in the uterus of fat-2 and fat-3 mutants. In addition, transgenic fat-2 mutant expressing a GFP fusion protein of vitellogenin-2 (a yolk lipoprotein) revealed that the enhanced CARS signal colocalized with the GFP signal, which suggests that the nondroplet-like structure is primarily due to the accumulation of yolk lipoproteins. Together, this study implies that CARS microscopy is a potential tool to study the distribution of yolk lipoproteins, in addition to lipid droplets, in live animals.

  20. Emerging Roles for Cholesterol and Lipoproteins in Lung Disease

    OpenAIRE

    Gowdy, Kymberly M; Fessler, Michael B.

    2012-01-01

    Dyslipidemia, the condition of elevated serum triglycerides, elevated low-density lipoprotein cholesterol, and/or low high-density lipoprotein cholesterol, is a public health problem of growing concern. Dyslipidemia clusters with other disorders of the metabolic syndrome that together influence, and may derive from, chronic inflammation. While best recognized as a risk factor for atherosclerotic cardiovascular disease, lipid dysregulation has recently been shown to influence a variety of dise...

  1. A clustering analysis of lipoprotein diameters in the metabolic syndrome

    OpenAIRE

    Frazier-Wood Alexis C; Glasser Stephen; Garvey W Timothy; Kabagambe Edmond K; Borecki Ingrid B; Tiwari Hemant K; Tsai Michael Y; Hopkins Paul N; Ordovas Jose M; Arnett Donna K

    2011-01-01

    Abstract Background The presence of smaller low-density lipoproteins (LDL) has been associated with atherosclerosis risk, and the insulin resistance (IR) underlying the metabolic syndrome (MetS). In addition, some research has supported the association of very low-, low- and high-density lipoprotein (VLDL HDL) particle diameters with components of the metabolic syndrome (MetS), although this has been the focus of less research. We aimed to explore the relationship of VLDL, LDL and HDL diamete...

  2. Increased transvascular low density lipoprotein transport in insulin dependent diabetes

    DEFF Research Database (Denmark)

    Kornerup, Karen; Nordestgaard, Børge Grønne; Feldt-Rasmussen, Bo;

    2003-01-01

    accumulation and thus atherosclerosis. METHODS: We used an in vivo method for measurement of transvascular transport of low density lipoprotein (LDL) and applied it in 24 patients with insulin dependent diabetes mellitus (type 1) and in 30 healthy controls. LDL was individually sampled and autologous 131...... be increased in patients with type 1 diabetes. This suggests that lipoprotein flux into the arterial wall is increased in people with type 1 diabetes, possibly explaining accelerated development of atherosclerosis....

  3. Lipoprotein particle concentrations in children and adults following kawasaki disease

    OpenAIRE

    Lin, J.; S. Jain; X. Sun; Liu, V; Sato, YZ; Jimenez-Fernandez, S; Newfield, RS; Pourfarzib, R; Tremoulet, AH; Gordon, JB; Daniels, LB; Burns, JC

    2014-01-01

    Objective: To test the hypothesis that children and adults with a history of Kawasaki disease (KD) are more likely to have abnormal lipoprotein particle profiles that could place them at increased risk for developing atherosclerosis later in life. Study design: Fasting serum samples were obtained from 192 children and 63 adults with history of KD and 90 age-similar healthy controls. Lipoprotein particle concentrations and sizes were measured by nuclear magnetic resonance spectroscopy (LipoSci...

  4. DNA Microarray Assessment of Putative Borrelia burgdorferi Lipoprotein Genes

    OpenAIRE

    Liang, Fang Ting; Nelson, F. Kenneth; Fikrig, Erol

    2002-01-01

    A DNA microarray containing fragments of 137 Borrelia burgdorferi B31 putative lipoprotein genes was used to examine Lyme disease spirochetes. DNA from B. burgdorferi sensu stricto B31, 297, and N40; Borrelia garinii IP90; and Borrelia afzelii P/Gau was fluorescently labeled and hybridized to the microarray, demonstrating the degree to which the individual putative lipoprotein genes were conserved among the genospecies. These data show that a DNA microarray can globally examine the genes enco...

  5. Mechanism of action of gemfibrozil on lipoprotein metabolism.

    OpenAIRE

    Saku, K; Gartside, P S; Hynd, B A; Kashyap, M L

    1985-01-01

    Gemfibrozil is a potent lipid regulating drug whose major effects are to increase plasma high density lipoproteins (HDL) and to decrease plasma triglycerides (TG) in a wide variety of primary and secondary dyslipoproteinemias. Its mechanism of action is not clear. Six patients with primary familial endogenous hypertriglyceridemia with fasting chylomicronemia (type V lipoprotein phenotype) with concurrent subnormal HDL cholesterol levels (HDL deficiency) were treated initially by diet and once...

  6. Lipoprotein Particle Concentrations in Children and Adults following Kawasaki Disease

    OpenAIRE

    J. Lin; Jain, S; X. Sun; Liu, V.; Sato, YZ; Jimenez-Fernandez, S; Newfield, RS; Pourfarzib, R; Tremoulet, AH; Gordon, JB; Daniels, LB; Burns, JC

    2014-01-01

    Objective: To test the hypothesis that children and adults with a history of Kawasaki disease (KD) are more likely to have abnormal lipoprotein particle profiles that could place them at increased risk for developing atherosclerosis later in life. Study design: Fasting serum samples were obtained from 192 children and 63 adults with history of KD and 90 age-similar healthy controls. Lipoprotein particle concentrations and sizes were measured by nuclear magnetic resonance spectroscopy (LipoSci...

  7. Lipoprotein particle concentrations in children and adults following kawasaki disease

    OpenAIRE

    J. Lin; Jain, S; X. Sun; Liu, V.; Sato, YZ; Jimenez-Fernandez, S; Newfield, RS; Pourfarzib, R; Tremoulet, AH; Gordon, JB; Daniels, LB; Burns, JC

    2014-01-01

    © 2014 Elsevier Inc. Objective To test the hypothesis that children and adults with a history of Kawasaki disease (KD) are more likely to have abnormal lipoprotein particle profiles that could place them at increased risk for developing atherosclerosis later in life. Study design Fasting serum samples were obtained from 192 children and 63 adults with history of KD and 90 age-similar healthy controls. Lipoprotein particle concentrations and sizes were measured by nuclear magnetic resonance sp...

  8. Serum lipoprotein lipase mass: Clinical significance of its measurement

    OpenAIRE

    Kobayashi, Junji; Nohara, Atsushi; Kawashiri, Masaaki; Inazu, Akihiro; Koizumi, Junji; Nakajima, Katsuyuki; Mabuchi, Hiroshi

    2007-01-01

    Lipoprotein lipase (LPL) is a lipolytic enzyme involved in catalyzing hydrolysis of triglycerides (TG) in chylomicrons and very low-density lipoprotein (VLDL) particles. Over the last decade, increasing attention has been paid to the clinical significance of measuring serum LPL protein mass without heparin injection to the study subjects. In earlier studies, this marker was utilized to classify LPL deficient subjects, which is an extremely rare metabolic disorder with a frequency of one in on...

  9. Lipoprotein lipase links dietary fat to solid tumor cell proliferation

    OpenAIRE

    Kuemmerle, Nancy B.; Rysman, Evelien; Lombardo, Portia S.; Flanagan, Alison J.; Lipe, Brea C.; Wells, Wendy A.; Pettus, Jason R.; Froehlich, Heather M.; Memoli, Vincent A.; Morganelli, Peter M.; Swinnen, Johannes V.; Timmerman, Luika A.; Chaychi, Leila; Fricano, Catherine J.; Eisenberg, Burton L.

    2011-01-01

    Many types of cancer cells require a supply of fatty acids (FA) for growth and survival, and interrupting de novo FA synthesis in model systems causes potent anticancer effects. We hypothesized that, in addition to synthesis, cancer cells may obtain pre-formed, diet-derived fatty acids by uptake from the bloodstream. This would require hydrolytic release of FA from triglyceride in circulating lipoprotein particles by the secreted enzyme lipoprotein lipase (LPL), and the expression of CD36, th...

  10. Interfacial Tension and Surface Pressure of High Density Lipoprotein, Low Density Lipoprotein, and Related Lipid Droplets

    DEFF Research Database (Denmark)

    Ollila, O. H. S.; Lamberg, A.; Lehtivaara, M.;

    2012-01-01

    Lipid droplets play a central role in energy storage and metabolism on a cellular scale. Their core is comprised of hydrophobic lipids covered by a surface region consisting of amphiphilic lipids and proteins. For example, high and low density lipoproteins (HDL and LDL, respectively......) are essentially lipid droplets surrounded by specific proteins, their main function being to transport cholesterol. Interfacial tension and surface pressure of these particles are of great interest because they are related to the shape and the stability of the droplets and to protein adsorption at the interface...

  11. High-density lipoprotein cholesterol: How High

    Directory of Open Access Journals (Sweden)

    G Rajagopal

    2012-01-01

    Full Text Available The high-density lipoprotein cholesterol (HDL-C is considered anti-atherogenic good cholesterol. It is involved in reverse transport of lipids. Epidemiological studies have found inverse relationship of HDL-C and coronary heart disease (CHD risk. When grouped according to HDL-C, subjects having HDL-C more than 60 mg/dL had lesser risk of CHD than those having HDL-C of 40-60 mg/dL, who in turn had lesser risk than those who had HDL-C less than 40 mg/dL. No upper limit for beneficial effect of HDL-C on CHD risk has been identified. The goals of treating patients with low HDL-C have not been firmly established. Though many drugs are known to improve HDL-C concentration, statins are proven to improve CHD risk and mortality. Cholesteryl ester transfer protein (CETP is involved in metabolism of HDL-C and its inhibitors are actively being screened for clinical utility. However, final answer is still awaited on CETP-inhibitors.

  12. Lipoprotein(a in Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Michele Malaguarnera

    2013-01-01

    Full Text Available Lipoprotein(a (Lp(a is an LDL-like molecule consisting of an apolipoprotein B-100 (apo(B-100 particle attached by a disulphide bridge to apo(a. Many observations have pointed out that Lp(a levels may be a risk factor for cardiovascular diseases. Lp(a inhibits the activation of transforming growth factor (TGF and contributes to the growth of arterial atherosclerotic lesions by promoting the proliferation of vascular smooth muscle cells and the migration of smooth muscle cells to endothelial cells. Moreover Lp(a inhibits plasminogen binding to the surfaces of endothelial cells and decreases the activity of fibrin-dependent tissue-type plasminogen activator. Lp(a may act as a proinflammatory mediator that augments the lesion formation in atherosclerotic plaques. Elevated serum Lp(a is an independent predictor of coronary artery disease and myocardial infarction. Furthermore, Lp(a levels should be a marker of restenosis after percutaneous transluminal coronary angioplasty, saphenous vein bypass graft atherosclerosis, and accelerated coronary atherosclerosis of cardiac transplantation. Finally, the possibility that Lp(a may be a risk factor for ischemic stroke has been assessed in several studies. Recent findings suggest that Lp(a-lowering therapy might be beneficial in patients with high Lp(a levels. A future therapeutic approach could include apheresis in high-risk patients in order to reduce major coronary events.

  13. Dissecting the proteome of lipoproteins: New biomarkers for cardiovascular diseases?

    Directory of Open Access Journals (Sweden)

    Anne von Zychlinski

    2015-06-01

    Full Text Available Proteomics has proven to be a powerful tool for the characterization of lipoproteins and has provided important insights into the biochemistry and pathophysiology of various lipoprotein classes. It has significantly contributed to the way we now see lipoproteins as complex particles not only involved in lipid transport and exchange, but also in processes such as immune response, inflammation and wound healing. Ongoing proteomics research is focussing on the identification of new candidate markers for cardiovascular disease, the leading cause of death worldwide. The ratio between good cholesterol (high density lipoprotein and bad cholesterol (low density lipoprotein is routinely used to estimate an individual’s risk for developing premature coronary heart disease. While statin therapy has proven effects in reducing cardiovascular events, other therapies such as resins, fibrates and niacin have failed to substantially reduce cardiovascular risk. Thus new targets and candidate biomarkers for risk assessment and for the development of alternative drugs and treatments of disease are needed. Here we review the recent findings in lipoprotein proteomics with the main emphasis on studies that differentially displayed various states of diseases and on new targeted, high throughput strategies with the capability to translate discovery findings into the clinical context of large cohort analyzes.

  14. Mechanisms and signiifcance of lipoprotein(a) in hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Jing-Ting Jiang; Chang-Ping Wu; Ning Xu; Xue-Guang Zhang

    2009-01-01

    BACKGROUND: The liver plays a key role in the metabolism of plasma apolipoproteins, endogenous lipids and lipoproteins. Hepatocellular carcinoma is one of the most common fatal malignant tumors in China and in other Southeast Asian countries. It has been demonstrated that plasma lipid proifles are changed in liver cancer. DATA SOURCES: A MEDLINE database search was performed to identify relevant articles using the keywords "hepatocellular carcinoma" and "lipoprotein(a)". The search was conducted and research articles were reviewed from 1960 to 2008. RESULTS: Production and homeostasis of lipids, apo-lipoproteins and lipoproteins depend on the integrity of hepatocellular functions, which ensures normal lipid and lipoprotein metabolismin vivo. When hepatocellular injury or liver cancer occurs these processes can be impaired. It has been suggested that plasma levels of apolipoprotein(a) (apo(a)) and/or lipoprotein(a) (Lp(a)) may be considered as sensitive markers of hepatic impairment. CONCLUSIONS: Plasma levels of apo(a) and Lp(a) display signiifcant correlations with hepatic status. Most studies demonstrated that the plasma levels of apo(a) and Lp(a) can be considered as an additional clinical index of liver function.

  15. Recent advances in lipoprotein and atherosclerosis: nutrigenomic approach

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, S.; Ortega, A.; Varela, L.; Bermudez, B.; Muriana, F. J. G.; Abaia, R.

    2009-07-01

    Atherosclerosis is a disease in which multiple factors contribute to the degeneration of the vascular wall. Many risk factors have been identified as having influence on the progression of atherosclerosis among them, the type of diet. Multifactorial interaction among lipoproteins, vascular wall cells, and inflammatory mediators has been recognised as the basis of atherogenesis. Dietary intake affects lipoprotein concentration and composition providing risk or protection at several stages of atherosclerosis. More intriguingly, it has been demonstrated that the extent to which each lipid or lipoprotein is associated with cardiovascular disease depends on the time to last meal; thus, postprandial lipoproteins, main lipoproteins in blood after a high-fat meal, have been shown to strongly influence atherogenesis. As a complex biological process, the full cellular and molecular characterization of atherosclerosis derived by diet, calls for application of the newly developing omics techniques of analysis. This review will considered recent studies using high-throughput technologies and a nutrigenomic approach to reveal the patho-physiological effects that the fasting and postprandial lipoproteins may exert on the vascular wall. (Author) 55 refs.

  16. The use of transgenic animals to study lipoprotein metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, E.M.; Plump, A.S.

    1993-12-01

    The application of transgenic technology to lipoprotein metabolism and atherosclerosis was first reported in 1988. Today, a large percentage of the genes involved in lipoprotein metabolism have been overexpressed in mice, and a substantial number of these same genes have been disrupted by homologous recombination in embryonic stem (ES) cells. The utility of animal models of lipoprotein metabolism and atherosclerosis is far-reaching given the complex nature of these systems. There are at least 17 known genes directly involved in lipoprotein metabolism and likely dozens more may be involved. This massive network of interacting factors has necessitated the development of in vivo systems which can be subject to genetic manipulation. The power of overexpression is obvious: elucidating function in a relatively controlled genetic environment in which the whole system is present and operational. The not-so-obvious problem with transgenics is ``background,`` or for purposes of the current discussion, the mouse`s own lipoprotein system. With the advent of gene knockout, we have been given the ability to overcome ``background.`` By recreating the genetic complement of the mouse we can alter a system in essentially any manner desired. As unique tools, and in combination with one another, the overexpression of foreign genes and the targeted disruption or alteration of endogenous genes has already and will continue to offer a wealth of information on the biology of lipoprotein metabolism and its effect on atherosclerosis susceptibility.

  17. The Swedish mutant barley collection

    International Nuclear Information System (INIS)

    Full text: The Swedish mutation research programme in barley began about 50 years ago and has mainly been carried out at Svaloev in co-operation with the institute of Genetics at the University of Lund. The collection has been produced from different Swedish high-yielding spring barley varieties, using the following mutagens: X-rays, neutrons, several organic chemical compounds such as ethyleneimine, several sulfonate derivatives and the inorganic chemical mutagen sodium azide. Nearly 10,000 barley mutants are stored in the Nordic Gene Bank and documented in databases developed by Udda Lundquist, Svaloev AB. The collection consists of the following nine categories with 94 different types of mutants: 1. Mutants with changes in the spike and spikelets; 2. Changes in culm length and culm composition; 3. Changes in growth types; 4. Physiological mutants; 5. Changes in awns; 6. Changes in seed size and shape; 7. Changes in leaf blades; 8. Changes in anthocyanin and colour; 9. Resistance to barley powdery mildew. Barley is one of the most thoroughly investigated crops in terms of induction of mutations and mutation genetics. So far, about half of the mutants stored at the Nordic Gene Bank, have been analysed genetically; They constitute, however, only a minority of the 94 different mutant types. The genetic analyses have given valuable insights into the mutation process but also into the genetic architecture of various characters. A number of mutants of two-row barley have been registered and commercially released. One of the earliest released, Mari, an early maturing, daylength neutral, straw stiff mutant, is still grown in Iceland. The Swedish mutation material has been used in Sweden, but also in other countries, such as Denmark, Germany, and USA, for various studies providing a better understanding of the barley genome. The collection will be immensely valuable for future molecular genetical analyses of clone mutant genes. (author)

  18. Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yanbo; Thyagarajan, Narmadaa; Coady, Breanne M.; Brown, Robert J., E-mail: rbrown@mun.ca

    2014-09-05

    Highlights: • Lipoprotein hydrolysis products were produced by lipoprotein lipase. • Hydrolysis products lowers expression of macrophage cholesterol transporters. • Hydrolysis products reduces expression of select nuclear receptors. • Fatty acid products lowers cholesterol transporters and select nuclear receptors. • Fatty acid products reduces cholesterol efflux from macrophages. - Abstract: Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL.

  19. Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase

    International Nuclear Information System (INIS)

    Highlights: • Lipoprotein hydrolysis products were produced by lipoprotein lipase. • Hydrolysis products lowers expression of macrophage cholesterol transporters. • Hydrolysis products reduces expression of select nuclear receptors. • Fatty acid products lowers cholesterol transporters and select nuclear receptors. • Fatty acid products reduces cholesterol efflux from macrophages. - Abstract: Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL

  20. Functional characterization of two low-density lipoprotein receptor gene mutations in two Chinese patients with familial hypercholesterolemia.

    Directory of Open Access Journals (Sweden)

    Haihong Wang

    Full Text Available Familial hypercholesterolemia (FH is an autosomal dominant disease that primarily results from mutations in the low-density lipoprotein receptor (LDLR gene. We investigated two unrelated Chinese FH patients using gene screening and functional analysis to reveal the pathogenicity and the mechanism by which these mutations cause FH.First, the LDLR gene was sequenced in these patients. Then, mutant receptors were transfected into human embryo kidney 293 (HEK-293 cells, and a confocal laser-scanning microscope was used to observe the localization of mutant proteins. Further, the expression and the internalization activity were analyzed by flow cytometry. Finally, LDLR protein expression and stability was detected by western blot.Two different LDLR class 2B mutations were detected in two patients. The C201F mutation is a known mutation. However, the G615V mutation is novel. Flow cytometry showed that the expression and internalization activity of the mutant LDLRs were reduced to 73.6% and 82.6% for G615V and 33.2% and 33.5% for C201F, respectively.This study identified two LDLR mutations in Chinese patients with FH and analyzed the relationship between the genotype and phenotype of these patients. We found that these mutant LDLRs were defective in transport, which led to a reduction in cholesterol clearance. These results increase our understanding of the mutational spectrum of FH in the Chinese population.

  1. Pistachio intake increases high density lipoprotein levels and inhibits low-density lipoprotein oxidation in rats.

    Science.gov (United States)

    Aksoy, Nur; Aksoy, Mehmet; Bagci, Cahit; Gergerlioglu, H Serdar; Celik, Hakim; Herken, Emine; Yaman, Abdullah; Tarakcioglu, Mehmet; Soydinc, Serdar; Sari, Ibrahim; Davutoglu, Vedat

    2007-05-01

    There is increasing evidence that nuts have protective effects against coronary artery disease by improving lipid profile and inhibiting lipid oxidation. However, data about pistachio nuts are limited, and to our knowledge, there is no study investigating the effects of pistachio intake on lipid oxidation and serum antioxidant levels. This study, therefore, sought to determine the effects of pistachio intake on serum lipids and determine whether consumption of pistachio would alter serum antioxidant levels. Rats were randomly divided into three groups (n=12 for each): control group fed basic diet for 10 weeks and treated groups fed basic diet plus pistachio which constituted 20% and 40% of daily caloric intake, respectively. Consumption of pistachio as 20% of daily caloric intake increased high-density lipoprotein (HDL) levels and decreased total cholesterol (TC)/HDL ratio, compared with those not taking pistachio. However, TC, low-density lipoprotein (LDL) cholesterol and triglyceride levels were unaffected by pistachio consumption. Consumption of pistachio as 20% of daily caloric intake increased serum paraoxonase activity by 35% and arylesterase activity by 60%, which are known to inhibit LDL cholesterol oxidation, compared with the control group. However, increased antioxidant activity was blunted when pistachio intake was increased to 40% of daily caloric intake. In conclusion, the present results show that consumption of pistachio as 20% of daily caloric intake leads to significant improvement in HDL and TC/HDL ratio and inhibits LDL cholesterol oxidation. These results suggest that pistachio may be beneficial for both prevention and treatment of coronary artery disease.

  2. Mutants of alfalfa mosaic virus

    International Nuclear Information System (INIS)

    In this thesis the isolation and characterization of a number of mutants of alfalfa mosaic virus, a plant virus with a coat protein dependent genome, is described. Thermo-sensitive (ts) mutants were selected since, at least theoretically, ts mutations can be present in all virus coded functions. It was found that a high percentage of spontaneous mutants, isolated because of their aberrant symptoms, were ts. The majority of these isolates could grow at the non-permissive temperature in the presence of a single wild type (wt) component. To increase the mutation rate virus preparations were treated with several mutagens. After nitrous acid treatment or irradiation with ultraviolet light, an increase in the level of mutations was observed. UV irradiation was preferred since it did not require large amounts of purified viral components. During the preliminary characterization of potential ts mutants the author also obtained one structural and several symptom mutants which were analysed further (chapter 7, 8 and 9). The properties of the ts mutants are described in chapter 3-7. (Auth.)

  3. The NlpD lipoprotein is a novel Yersinia pestis virulence factor essential for the development of plague.

    Directory of Open Access Journals (Sweden)

    Avital Tidhar

    Full Text Available Yersinia pestis is the causative agent of plague. Previously we have isolated an attenuated Y. pestis transposon insertion mutant in which the pcm gene was disrupted. In the present study, we investigated the expression and the role of pcm locus genes in Y. pestis pathogenesis using a set of isogenic surE, pcm, nlpD and rpoS mutants of the fully virulent Kimberley53 strain. We show that in Y. pestis, nlpD expression is controlled from elements residing within the upstream genes surE and pcm. The NlpD lipoprotein is the only factor encoded from the pcm locus that is essential for Y. pestis virulence. A chromosomal deletion of the nlpD gene sequence resulted in a drastic reduction in virulence to an LD(50 of at least 10(7 cfu for subcutaneous and airway routes of infection. The mutant was unable to colonize mouse organs following infection. The filamented morphology of the nlpD mutant indicates that NlpD is involved in cell separation; however, deletion of nlpD did not affect in vitro growth rate. Trans-complementation experiments with the Y. pestis nlpD gene restored virulence and all other phenotypic defects. Finally, we demonstrated that subcutaneous administration of the nlpD mutant could protect animals against bubonic and primary pneumonic plague. Taken together, these results demonstrate that Y. pestis NlpD is a novel virulence factor essential for the development of bubonic and pneumonic plague. Further, the nlpD mutant is superior to the EV76 prototype live vaccine strain in immunogenicity and in conferring effective protective immunity. Thus it could serve as a basis for a very potent live vaccine against bubonic and pneumonic plague.

  4. Experimental hypothyroidism modulates the expression of the low density lipoprotein receptor by the liver

    International Nuclear Information System (INIS)

    The effect of exprimental hypothyroidism of the catabolism of plasma lipoproteins and on the expression of low density lipoprotein receptors by the liver was investigated in rats made hypothyroid by surgery. The animals developed mild hypercholesterolemia, mainly due to an increase of plasma low density lipoprotein, while other lipoprotein classes were only marginally affected. Kinetic studies using (125I)LDL indicated that a decreased fractional catabolic rate of the lipoprotein was responsible for this finding in agreement with the in vitro observation of a reduced binding of lipoproteins to liver membranes from hyperthyroid rats and with the demonstrations, by ligand blotting analysis, of a decreasd expression of lipoprotein receptors in liver membranes. These data suggest that hypothyroidism affects lipoprotein distribution also by decreasing the catabolism of low density lipoproteins by the liver (author)

  5. Gutscheine und Protektionismus / Gerald Braun

    Index Scriptorium Estoniae

    Braun, Gerald

    2016-01-01

    Euroopa Kohtu otsusest, mis käsitleb küsimust, millistel tingimustel võivad tööandjad väljastada oma töötajatele maksusoodustusega talonge, mida saab kasutada majutuseks, meelelahutuseks ja/või toitlustuseks (C‑179/14). Vt. ka lk. 439-440

  6. Achieving secondary prevention low-density lipoprotein particle concentration goals using lipoprotein cholesterol-based data.

    Directory of Open Access Journals (Sweden)

    Simon C Mathews

    Full Text Available BACKGROUND: Epidemiologic studies suggest that LDL particle concentration (LDL-P may remain elevated at guideline recommended LDL cholesterol goals, representing a source of residual risk. We examined the following seven separate lipid parameters in achieving the LDL-P goal of <1000 nmol/L goal for very high risk secondary prevention: total cholesterol to HDL cholesterol ratio, TC/HDL, <3; a composite of ATP-III very high risk targets, LDL-C<70 mg/dL, non-HDL-C<100 mg/dL and TG<150 mg/dL; a composite of standard secondary risk targets, LDL-C<100, non-HDL-C<130, TG<150; LDL phenotype; HDL-C ≥ 40; TG<150; and TG/HDL-C<3. METHODS: We measured ApoB, ApoAI, ultracentrifugation lipoprotein cholesterol and NMR lipoprotein particle concentration in 148 unselected primary and secondary prevention patients. RESULTS: TC/HDL-C<3 effectively discriminated subjects by LDL-P goal (F = 84.1, p<10(-6. The ATP-III very high risk composite target (LDL-C<70, nonHDL-C<100, TG<150 was also effective (F = 42.8, p<10(-5. However, the standard secondary prevention composite (LDL-C<100, non-HDL-C<130, TG<150 was also effective but yielded higher LDL-P than the very high risk composite (F = 42.0, p<10(-5 with upper 95% confidence interval of LDL-P less than 1000 nmol/L. TG<150 and TG/HDL-C<3 cutpoints both significantly discriminated subjects but the LDL-P upper 95% confidence intervals fell above goal of 1000 nmol/L (F = 15.8, p = 0.0001 and F = 9.7, p = 0.002 respectively. LDL density phenotype neared significance (F = 2.85, p = 0.094 and the HDL-C cutpoint of 40 mg/dL did not discriminate (F = 0.53, p = 0.47 alone or add discriminatory power to ATP-III targets. CONCLUSIONS: A simple composite of ATP-III very high risk lipoprotein cholesterol based treatment targets or TC/HDL-C ratio <3 most effectively identified subjects meeting the secondary prevention target level of LDL-P<1000 nmol/L, providing a potential alternative to advanced lipid testing in many clinical

  7. Lipoprotein distribution and serum concentrations of 7α-hydroxy-4-cholesten-3-one and bile acids: effects of monogenic disturbances in high-density lipoprotein metabolism

    DEFF Research Database (Denmark)

    Steiner, Carine; Holleboom, Adriaan G; Karuna, Ratna;

    2012-01-01

    BA (bile acid) formation is considered an important final step in RCT (reverse cholesterol transport). HDL (high-density lipoprotein) has been reported to transport BAs. We therefore investigated the effects of monogenic disturbances in human HDL metabolism on serum concentrations and lipoprotein...... distributions of the major 15 BA species and their precursor C4 (7a-hydroxy-4-cholesten-3-one). In normolipidaemic plasma, approximately 84%, 11% and 5% of BAs were recovered in the LPDS (lipoprotein-depleted serum), HDL and the combined LDL (low-density lipoprotein)/VLDL (very-low-density lipoproteins...

  8. Metabolism of apolipoproteins B-48 and B-100 of triglyceride-rich lipoproteins in normal and lipoprotein lipase-deficient humans.

    OpenAIRE

    Stalenhoef, A.F.; Malloy, M J; Kane, J P; Havel, R J

    1984-01-01

    The metabolism of apolipoproteins B-48 and B-100 (apo B-48 and B-100) in large triglyceride-rich lipoproteins (300 to 1500 A in diameter) has been compared in three normal subjects and two subjects with genetically determined deficiency of lipoprotein lipase. The triglyceride-rich lipoproteins were obtained from a lipoprotein lipase-deficient donor 4 hr after a fat-rich meal in order to obtain chylomicrons (containing apo B-48) and very low density lipoproteins (VLDL) (containing apo B-100), ...

  9. New and emerging regulators of intestinal lipoprotein secretion.

    Science.gov (United States)

    Xiao, Changting; Dash, Satya; Morgantini, Cecilia; Lewis, Gary F

    2014-04-01

    Overproduction of hepatic apoB100-containing VLDL particles has been well documented in animal models and in humans with insulin resistance such as the metabolic syndrome and type 2 diabetes, and contributes to the typical dyslipidemia of these conditions. In addition, postprandial hyperlipidemia and elevated plasma concentrations of intestinal apoB48-containing chylomicron and chylomicron remnant particles have been demonstrated in insulin resistant states. Intestinal lipoprotein production is primarily determined by the amount of fat ingested and absorbed. Until approximately 10 years ago, however, relatively little attention was paid to the role of the intestine itself in regulating the production of triglyceride-rich lipoproteins (TRL) and its dysregulation in pathological states such as insulin resistance. We and others have shown that insulin resistant animal models and humans are characterized by overproduction of intestinal apoB48-containing lipoproteins. Whereas various factors are known to regulate hepatic lipoprotein particle production, less is known about factors that regulate the production of intestinal lipoprotein particles. Monosacharides, plasma free fatty acids (FFA), resveratrol, intestinal peptides (e.g. GLP-1 and GLP-2), and pancreatic hormones (e.g. insulin) have recently been shown to be important regulators of intestinal lipoprotein secretion. Available evidence in humans and animal models strongly supports the concept that the small intestine is not merely an absorptive organ but rather plays an active role in regulating the rate of production of chylomicrons in fed and fasting states. Metabolic signals in insulin resistance and type 2 diabetes and in some cases an aberrant intestinal response to these factors contribute to the enhanced formation and secretion of TRL. Understanding the regulation of intestinal lipoprotein production is imperative for the development of new therapeutic strategies for the prevention and treatment of

  10. Low density lipoproteins mediated nanoplatforms for cancer targeting

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Anupriya; Jain, Keerti; Kesharwani, Prashant, E-mail: prashant_pharmacy04@rediffmail.com; Jain, Narendra K., E-mail: jnarendr@yahoo.co.in [Dr. H. S. Gour University, Pharmaceutics Research Laboratory, Department of Pharmaceutical Sciences (India)

    2013-09-15

    Chemotherapy is a foremost remedial approach for the treatment of localized and metastasized tumors. In order to explore new treatment modalities for cancer, it is important to identify qualitative or quantitative differences in metabolic processes between normal and malignant cells. One such difference may be that of increased receptor-mediated cellular uptake of low density lipoproteins (LDLs) by cancer cells. Lipoproteins in general and specifically LDL are ideal candidates for loading and delivering cancer therapeutic and diagnostic agents due to their biocompatibility. By mimicking the endogenous shape and structure of lipoproteins, the reconstituted lipoproteins can remain in circulation for an extended period of time, while largely evading the reticuloendothelial cells in the body's defenses. In this account, we review the field of low density inspired nanoparticles in relation to the delivery of cancer imaging and therapeutic agents. LDL has instinctive cancer targeting potential and has been used to incorporate various lipophillic molecules to transport them to tumors. Nature's method of rerouting LDL provides a strategy to extend the cancer targeting potential of lipoproteins far off its constricted purview. In this review, we have discussed the various aspects of LDL including its role in cancer imaging and chemotherapy in retrospect and prospect and current efforts aimed to further improve the delivery efficacy of LDL-drug complexes with reduced chances of drug resistance leading to optimal drug delivery. This review provides a strong support for the concept of using LDL as a drug carrier.

  11. Lipoproteins tethered dendrimeric nanoconstructs for effective targeting to cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Anupriya; Jain, Keerti, E-mail: keertijain02@gmail.com; Mehra, Neelesh Kumar, E-mail: neelesh81mph@gmail.com; Jain, N. K., E-mail: dr.jnarendr@gmail.com [Dr. H. S. Gour University, Pharmaceutics Research Laboratory, Department of Pharmaceutical Sciences (India)

    2013-10-15

    In the present investigation, poly (propylene imine) dendrimers up to fifth generation (PPI G5.0) were synthesized using ethylene diamine and acrylonitrile. Lipoproteins (high-density lipoprotein; HDL and low-density lipoprotein; LDL) were isolated from human plasma by discontinuous density gradient ultracentrifugation, characterized and tethered to G5.0 PPI dendrimers to construct LDL- and HDL-conjugated dendrimeric nanoconstructs for tumor-specific delivery of docetaxel. Developed formulations showed sustained release characteristics in in vitro drug release and in vivo pharmacokinetic studies. The cancer targeting potential of lipoprotein coupled dendrimers was investigated by ex vivo cytotoxicity and cell uptake studies using human hepatocellular carcinoma cell lines (HepG2 cells) and biodistribution studies in albino rats of Sprague-Dawley strain. Lipoprotein anchored dendrimeric nanoconstructs showed significant uptake by cancer cells as well as higher biodistribution of docetaxel to liver and spleen. It is concluded that these precisely synthesized engineered dendrimeric nanoconstructs could serve as promising drug carrier for fighting with the fatal disease, i.e., cancer, attributed to their defined targeting and therapeutic potential.

  12. New micromethod for measuring cholesterol in plasma lipoprotein fractions.

    Science.gov (United States)

    Bronzert, T J; Brewer, H B

    1977-11-01

    A method is described for the reliable, fast, and relatively inexpensive fractionation of plasma lipoproteins and quantitation of their cholesterol content. This procedure requires 350 microliter of plasma and can be completed within 3 h. Plasma lipoproteins (175 microliter of plasma) were prestained with Fat Red 7B and centrifuged (Beckman Airfuge) at plasma density (d = 1.006 kg/liter) and at a solvent density of 1.060 kg/liter, adjusted by adding solid KBr. Prestained centrifuged samples demonstrated the characteristic elevation of chylomicrons in phenotypes I and V, low-density lipoproteins of phenotype II, very-low-density lipoproteins in phenotype IV and V, and continuum of pink color throughout the centrifuge tube, diagnostic of the floating beta lipoprotein of type III. Centrifuged samples were separated into top and bottom fractions by aspiration. Cholesterol was quantitated with an enzymic oxygen-electrode analyzer (Beckman Cholesterol Analyzer). Correlation coefficients between cholesterol values for plasma from normal hyperlipidemic individuals obtained with the Beckman Analyzer vs. the Technicon AutoAnalyzer II and SMAC systems were 0.977 and 0.973, respectively.

  13. Deletion in the first cysteine-rich repeat of low density lipoprotein receptor impairs its transport but not lipoprotein binding in fibroblasts from a subject with familial hypercholesterolemia

    International Nuclear Information System (INIS)

    The ligand-binding domain of the low density lipoprotein (LDL) receptor is composed of seven cysteine-rich repeats, each ∼ 40 amino acids long. Previous studies showed that if the first repeat of the ligand-binding domain (encoded by exon 2) is deleted, the receptor fails to bind an anti-LDL receptor monoclonal antibody (IgG-C7) but continues to bind LDL with high affinity. Cultured fibroblasts from a Black South African Xhosa patient (TT) with the clinical syndrome of homozygous familial hypercholesterolemia demonstrated high-affinity cell-surface binding of 125I-labeled LDL but not 125I-labeled IgG-C7. previous haplotype analysis, using 10 restriction fragment length polymorphic sites, suggested that the patient inherited two identical LDL receptor alleles. The polymerase chain reaction technique was used to selectively amplify exon 2 of the LDL receptor gene from this patient. Sequence analysis of the amplified fragment disclosed a deletion of six base pairs that removes two amino acids, aspartic acid and glycine, from the first cysteine-rich ligand binding repeat. The mutation creates a new Pst I restriction site that can be used to detect the deletion. The existence of this mutant allele confirms that the epitope of IgG-C7 is located in the first cysteine-rich repeat and that this repeat is not necessary for LDL binding. The mutant gene produced a normally sized 120-kilodalton LDL receptor precursor protein that matured to the 160-kilodalton form at less than one-fourth the normal rate

  14. Triglyceride-Rich Lipoproteins and Atherosclerotic Cardiovascular Disease

    DEFF Research Database (Denmark)

    Nordestgaard, Børge G

    2016-01-01

    Scientific interest in triglyceride-rich lipoproteins has fluctuated over the past many years, ranging from beliefs that these lipoproteins cause atherosclerotic cardiovascular disease (ASCVD) to being innocent bystanders. Correspondingly, clinical recommendations have fluctuated from a need...... to reduce levels to no advice on treatment. New insight in epidemiology now suggests that these lipoproteins, marked by high triglycerides, are strong and independent predictors of ASCVD and all-cause mortality, and that their cholesterol content or remnant cholesterol likewise are strong predictors...... of ASCVD. Of all adults, 27% have triglycerides >2 mmol/L (176 mg/dL), and 21% have remnant cholesterol >1 mmol/L (39 mg/dL). For individuals in the general population with nonfasting triglycerides of 6.6 mmol/L (580 mg/dL) compared with individuals with levels of 0.8 mmol/L (70 mg/dL), the risks were 5...

  15. Serum lipid & lipoprotein profiles of obese Chinese children.

    Science.gov (United States)

    Ho, T F; Paramsothy, S; Aw, T C; Yip, W C

    1996-03-01

    The serum lipid and lipoprotein levels of 59 obese Chinese children with a mean age of 13.0 years and mean relative weight of 164.2% were analysed. Between 40% to 54% of these children had elevated lipid and lipoprotein levels and about 78% had reduced high density lipoprotein (HDL) level when compared to healthy American and Japanese children. The obese children also had higher mean levels of total cholesterol (TC) and lower HDL compared to male adults in the local population. Those with elevated TC had higher mean relative weight (170% vs 159%, p obese children should be carefully screened and managed to prevent long term morbidity and mortality of coronary artery disease. PMID:10967982

  16. Influence of liver cancer on lipid and lipoprotein metabolism

    Directory of Open Access Journals (Sweden)

    Nilsson-Ehle Peter

    2006-03-01

    Full Text Available Abstract Liver plays a key role in the metabolism of plasma apolipoproteins, endogenous lipids and lipoproteins. Hepatocellular carcinoma (HCC is one of the most common fatal malignant tumors in China and in other Southeast Asian countries. This has been attributed to the high incidence of hepatitis B infection. Hepatitis B proteins, such as the hepatitis B X protein (HBx that is large hepatitis B surface protein could regulate transcription of many candidate genes for liver carcinogenesis. It has known that patients who suffered from acute hepatitis B could have lipid disorders such as decreased plasma level of high-density lipoproteins (HDL. Furthermore, aberrations of lipid metabolism are often seen in the chronic hepatitis B infection. Plasma lipid profiles could be changed under HCC. In majority of the reports in HCC, plasma levels of triglycerides (TG, cholesterol, free fatty acids (FFA, HDL, low-density lipoproteins (LDL, lipoprotein (a (Lp(a, apolipoprotein AI (apoAI and apoB were slight to significantly decreased, however, in some cases plasma levels of TG and Lp(a might be increased. It has been suggested that analysis of plasma levels of lipids, lipoproteins and apolipoproteins in the patients suffered from HCC reflects on the hepatic cellular impairment status. Studies revealed that alterations seen in the plasma levels of lipids, lipoproteins and apolipoproteins reflecting patients' pathologic conditions. Decreased serum levels of cholesterol and apoAI may indicate a poor prognosis. Human leukaemic cells and certain tumor tissues have a higher receptor-mediated uptake of HDL and LDL than the corresponding normal cells or tissues. LDL and HDL have therefore been proposed as a carrier for the water-insoluble anti-cancer agents.

  17. Prediction of lipoprotein signal peptides in Gram-negative bacteria

    DEFF Research Database (Denmark)

    Juncker, Agnieszka; Willenbrock, Hanni; Von Heijne, G.;

    2003-01-01

    from Gram-negatives, the HMM was able to identify 92.9% of the lipoproteins included in a Gram-positive test set. A genome search was carried out for 12 Gram-negative genomes and one Gram-positive genome. The results for Escherichia coli K12 were compared with new experimental data, and the predictions...... by the HMM agree well with the experimentally verified lipoproteins. A neural network-based predictor was developed for comparison, and it gave very similar results. LipoP is available as a Web server at www.cbs.dtu.dk/services/LipoP/....

  18. Improving lipoprotein profiles by liver-directed gene transfer of low density lipoprotein receptor gene in hypercholesterolaemia mice

    Indian Academy of Sciences (India)

    HAILONG OU; QINGHAI ZHANG; JIA ZENG

    2016-06-01

    The defect of low density lipoprotein receptor disturbs cholesterol metabolism and causes familial hypercholesterolaemia(FH). In this study, we directly delivered exogenousLdlrgene into the liver of FH model mice (Ldlr − / −) by lentiviral genetransfer system. The results showed that theLdlrgene controlled by hepatocyte-specific human thyroxine-binding globulin(TBG) promoter successfully and exclusively expressed in livers. We found that, although, the content of high density lipopro-tein in serum was not significantly affected by theLdlrgene expression, the serum low density lipoprotein level was reducedby 46%, associated with a 30% and 28% decrease in triglyceride and total cholesterol, respectively, compared to uninjectedLdlr − / −mice. Moreover, the TBG directed expression ofLdlrsignificantly decreased the lipid accumulation in liver andreduced plaque burden in aorta (32%). Our results indicated that the hepatocyte-specific expression ofLdlrgene strikinglylowered serum lipid levels and resulted in amelioration of hypercholesterolaemia.

  19. Circulating lipoproteins are a crucial component of host defense against invasive Salmonella typhimurium infection.

    NARCIS (Netherlands)

    Netea, M.G.; Joosten, L.A.B.; Keuter, M.; Wagener, F.A.D.T.G.; Stalenhoef, A.F.H.; Meer, J.W.M. van der; Kullberg, B.J.

    2009-01-01

    BACKGROUND: Circulating lipoproteins improve the outcome of severe Gram-negative infections through neutralizing lipopolysaccharides (LPS), thus inhibiting the release of proinflammatory cytokines. METHODS/PRINCIPAL FINDINGS: Low density lipoprotein receptor deficient (LDLR-/-) mice, with a 7-fold i

  20. 21 CFR 866.5600 - Low-density lipoprotein immunological test system.

    Science.gov (United States)

    2010-04-01

    ... the low-density lipoprotein in serum and other body fluids. Measurement of low-density lipoprotein in serum may aid in the diagnosis of disorders of lipid (fat) metabolism and help to identify young...

  1. Lipoprotein lipase release from BFC-1 beta adipocytes. Effects of triglyceride-rich lipoproteins and lipolysis products.

    Science.gov (United States)

    Sasaki, A; Goldberg, I J

    1992-07-25

    Lipoprotein lipase (LPL), synthesized by adipocytes and myocytes, must be transported to the luminal endothelial cell surface where it then interacts with circulating lipoproteins. The first step in this extracellular LPL transport pathway is LPL release from the surface of LPL-synthesizing cells. Because hydrolysis of triglyceride (TG)-rich lipoproteins releases LPL from the apical surface of endothelial cells, we hypothesized that the same substances dissociate LPL from adipocytes. 125I-LPL was bound to the surface of brown adipocytes (BFC-1 beta). LPL binding to the adipocyte surface was greater than to endothelial cell surfaces. Using low concentrations of heparin, more LPL was released from endothelial cells than BFC-1 beta, suggesting that the affinity of LPL binding to the adipocytes was greater than LPL affinity for endothelial cells. Greater than 3-fold more LPL was released from the cell surface when very low density lipoproteins (VLDL) were added to culture medium containing 3% bovine serum albumin. LPL remaining on the cell surface decreased with VLDL addition. Endogenously produced LPL activity was also released from the cells by VLDL. Low and high density lipoproteins did not release 125I-LPL or LPL activity from the adipocytes. To assess whether lipolysis was necessary for LPL release, BFC-1 beta were incubated with TG-rich lipoproteins from a patient with apoCII deficiency. The apoCII-deficient lipoproteins did not release LPL unless an exogenous source of apoCII was added. Apolipoproteins E and Cs and high molar ratios of oleic acid:bovine serum albumin did not release surface-associated LPL. Lysolecithin (25 and 100 microM), but not lecithin, monoglycerides, or diglycerides, released adipocyte surface LPL. Because lysolecithin also released LPL during a 4 degrees C incubation, cellular metabolic functions are not required for LPL dissociation from the cells. Lysolecithin also inhibited LPL binding to endothelial cells; however, this effect was

  2. Wild Accessions and Mutant Resources

    DEFF Research Database (Denmark)

    Kawaguchi, Masayoshi; Sandal, Niels Nørgaard

    2014-01-01

    Lotus japonicus, Lotus burttii, and Lotus filicaulis are species of Lotus genus that are utilized for molecular genetic analysis such as the construction of a linkage map and QTL analysis. Among them, a number of mutants have been isolated from two wild accessions: L. japonicus Gifu B-129...

  3. Associations between airway hyperresponsiveness, obesity, and lipoproteins in a longitudinal cohort

    DEFF Research Database (Denmark)

    Rasmussen, Finn; Hancox, Robert; Nair, Parameswaran;

    2013-01-01

    . The present study investigated the association between airway hyperresponsiveness (AHR) to methacholine and body mass index (BMI) and plasma lipoproteins [low-density lipoprotein (LDL), high-density lipoprotein (HDL) and total cholesterol]. Methods Associations between AHR, BMI and plasma lipoproteins were...... assessed in a population-based cohort at ages 14 and 20 years. Results In unadjusted analyses, higher LDL cholesterol levels at age 14 were associated with AHR at age 20 in both sexes (P...

  4. Elucidation of the function of lipoprotein-sorting signals that determine membrane localization

    OpenAIRE

    Masuda, Kazuhiro; Matsuyama, Shin-ichi; Tokuda, Hajime

    2002-01-01

    Escherichia coli lipoproteins are anchored to the inner or outer membrane depending on the residue at position 2. Aspartate at this position makes lipoproteins specific to the inner membrane, whereas other residues cause the release of lipoproteins from the inner membrane in a manner dependent on both ATP binding cassette (ABC) transporter LolCDE and molecular chaperone LolA, followed by LolB-dependent localization in the outer membrane. The function of lipoprotein-sorting signals was examine...

  5. Apolipoprotein B-containing lipoprotein particle assembly: Lipid capacity of the nascent lipoprotein particle

    Energy Technology Data Exchange (ETDEWEB)

    Manchekar, Medha; Forte, Trudy M.; Datta, Geeta; Richardson, Paul E.; Segrest, Jere P.; Dashti, Nassrin

    2003-12-01

    We previously proposed that the N-terminal 1000 residue {beta}{alpha}{sub 1} domain of apolipoprotein B (apoB) forms a bulk lipid pocket homologous to that of lamprey lipovitellin (LV). In support of this ''lipid pocket'' hypothesis, apoB:1000 (residues 1-1000) was shown to be secreted by a stable transformant of McA-RH7777 cells as a monodisperse particle with HDL{sub 3} density and Stokes diameter of 112 {angstrom}. In contrast, apoB:931 (residues 1-931), missing only 69 residues of the sequence homologous to LV, was secreted as a particle considerably more dense than HDL with Stokes diameter of 110 {angstrom}. The purpose of the present study was to determine the stoichiometry of the lipid component of the apoB:931 and apoB:1000 particles. This was accomplished by metabolic labeling of cells with either [{sup 14}C]oleic acid or [{sup 3}H]glycerol followed by immunoprecipitation (IP) or nondenaturing gradient gel electrophoresis (NDGGE) of secreted lipoproteins and by immunoaffinity chromatography of secreted unlabeled lipoproteins. The [{sup 3}H]-labeled apoB:1000-containing particles, isolated by NDGGE, contained 50 phospholipids (PL) and 11 triacylglycerols (TAG) molecules per particle. In contrast, apoB:931-containing particles contained only a few molecules of PL and were devoid of TAG. The unlabeled apoB:1000-containing particles isolated by immunoaffinity chromatography and analyzed for lipid mass, contained 56 PL, 8 TAG, and 7 cholesteryl ester molecules per particle. The surface:core lipid ratio of apoB:1000-containing particles was approximately 4:1 and was not affected by incubation of cells with oleate. Although small amounts of microsomal triglyceride transfer protein (MTP) were associated with apoB:1000-containing particles, it never approached a 1:1 molar ratio of MTP to apoB. These results support a model in which: (1) the first 1000 amino acid residues of apoB are competent to complete the ''lipid pocket

  6. Relative atherogenicity and predictive value of non-high-density lipoprotein cholesterol for coronary heart disease

    Science.gov (United States)

    Although low-density lipoprotein cholesterol (LDL-C) is a well-established atherogenic factor for coronary heart disease, it does not completely represent the risk associated with atherogenic lipoproteins in the presence of high triglyceride (TG) levels. Constituent lipoproteins constituting non–hig...

  7. Identification of megalin/gp330 as a receptor for lipoprotein(a) in vitro

    DEFF Research Database (Denmark)

    Niemeier, A; Willnow, T; Dieplinger, H;

    1999-01-01

    Lipoprotein(a) [Lp(a)] is an atherogenic lipoprotein of unknown physiological function. The mechanism of Lp(a) atherogenicity as well as its catabolic pathways are only incompletely understood at present. In this report, we show that the low density lipoprotein receptor (LDLR) gene family member ...

  8. Pitavastatin versus Pravastatin in Reduction of Remnant Lipoprotein Cholesterol in Patients with Dyslipidemias.

    Science.gov (United States)

    Roever, Leonardo

    2016-05-01

    Remnant lipoproteins cholesterol are products of partially catabolized chylomicrons and very-low-density lipoprotein, from which some triglycerides have been removed. These particles are smaller and are believed to be strongly atherogenic. Elevated Remnant lipoproteins cholesterol levels were reported to be associated with endothelial dysfunction and atherosclerotic disease.

  9. Hyperglycemia-induced hyperinsulinemia acutely lowers plasma apolipoprotein B but not lipoprotein (a) in man

    NARCIS (Netherlands)

    Riemens, SC; Ligtenberg, JJM; Dullaart, RPF

    1997-01-01

    Acute hyperinsulinemia lowers plasma apolipoprotein B (apo B) and triglycerides by suppressing hepatic lipoprotein secretion and probably by enhancing catabolism of triglyceride-rich lipoproteins, but the effect of acute hyperinsulinemia on the plasma lipoprotein(a) (Lp(a)) level is unclear. We meas

  10. DMPD: Low density lipoprotein oxidation and its pathobiological significance. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 9261091 Low density lipoprotein oxidation and its pathobiological significance. Ste...inberg D. J Biol Chem. 1997 Aug 22;272(34):20963-6. (.png) (.svg) (.html) (.csml) Show Low density lipoprotein oxidation and its path...obiological significance. PubmedID 9261091 Title Low density lipoprotein oxidation and its path

  11. A Novel Anti-Inflammatory Effect for High Density Lipoprotein.

    Directory of Open Access Journals (Sweden)

    Scott J Cameron

    Full Text Available High density lipoprotein has anti-inflammatory effects in addition to mediating reverse cholesterol transport. While many of the chronic anti-inflammatory effects of high density lipoprotein (HDL are attributed to changes in cell adhesion molecules, little is known about acute signal transduction events elicited by HDL in endothelial cells. We now show that high density lipoprotein decreases endothelial cell exocytosis, the first step in leukocyte trafficking. ApoA-I, a major apolipoprotein of HDL, mediates inhibition of endothelial cell exocytosis by interacting with endothelial scavenger receptor-BI which triggers an intracellular protective signaling cascade involving protein kinase C (PKC. Other apolipoproteins within the HDL particle have only modest effects upon endothelial exocytosis. Using a human primary culture of endothelial cells and murine apo-AI knockout mice, we show that apo-AI prevents endothelial cell exocytosis which limits leukocyte recruitment. These data suggest that high density lipoprotein may inhibit diseases associated with vascular inflammation in part by blocking endothelial exocytosis.

  12. Interaction of low density lipoproteins with rat liver cells

    NARCIS (Netherlands)

    L. Harkes (Leendert)

    1985-01-01

    textabstractThe most marked conclusion is the establishment of the important role of non-parenchymal cells in the catabolism of the low density lipoproteins by the rat liver. Because the liver is responsible for 70-80% of the removal of LDL from blood this conclusion can be extended to total LDL tur

  13. Lifecycle of a Lipoprotein from a Biophysical Perspective

    Science.gov (United States)

    Rutledge, John C.; Huser, Thomas; Voss, John; Chan, James; Parikh, Atul

    The goal of our project was to understand how lipids and lipoproteins interact with cell membranes. This chapter will present the five major areas in which we have focused our attention on understanding how lipids and lipoproteins interact with cell membranes (Fig. 11.1): (1) triglycerides and vascular injury, (2) single lipoprotein analysis, (3) apolipoprotein E (apoE) conformation changes in the postprandial state, (4) triglyceride-rich lipoproteins (TGRLs) and endothelial cell inflammation, and (5) TGRL lipolysis products and monocyte activation. For over a hundred years, Western civilization has questioned how the food we eat translates into disease, and specifically atherosclerotic cardiovascular disease. Although most information indicates that this basic pathophysiological process is mediated through consumption of excess saturated fats, much remains unknown. After humans eat a meal, there is an elevation of triglycerides in the blood in the postprandial state. In normal individuals, triglycerides can rise after a meal by 50 to 100%. This has been documented many times in the past, including a paper by Hyson et al, (1998) [1]. In that study, normal healthy individuals were given a 40%-fat meal. Plasma triglycerides, which were modestly elevated initially, rose about 60% higher three to four hours after ingestion of the meal. Subsequently plasma triglycerides fell to baseline levels six hours after the meal. Even in these healthy individuals, a significant elevation of triglycerides was noted after ingestion of a moder ately high-fat meal.

  14. Lipoprotein(a) as a cardiovascular risk factor : current status

    NARCIS (Netherlands)

    Nordestgaard, Børge G; Chapman, M John; Ray, Kausik; Borén, Jan; Andreotti, Felicita; Watts, Gerald F; Ginsberg, Henry; Amarenco, Pierre; Catapano, Alberico; Descamps, Olivier S; Fisher, Edward; Kovanen, Petri T; Kuivenhoven, Jan Albert; Lesnik, Philippe; Masana, Luis; Reiner, Zeljko; Taskinen, Marja-Riitta; Tokgözoglu, Lale; Tybjærg-Hansen, Anne

    2010-01-01

    AIMS: The aims of the study were, first, to critically evaluate lipoprotein(a) [Lp(a)] as a cardiovascular risk factor and, second, to advise on screening for elevated plasma Lp(a), on desirable levels, and on therapeutic strategies. METHODS AND RESULTS: The robust and specific association between e

  15. [Residual risk: The roles of triglycerides and high density lipoproteins].

    Science.gov (United States)

    Grammer, Tanja; Kleber, Marcus; Silbernagel, Günther; Scharnagl, Hubert; März, Winfried

    2016-06-01

    In clinical trials, the reduction of LDL-cholesterol (LDL-C) with statins reduces the incidence rate of cardiovascular events by approximately one third. This means, that a sizeable "residual risk" remains. Besides high lipoprotein (a), disorders in the metabolism of triglyceride-rich lipoproteins and high density liproteins have been implicated as effectors of the residual risk. Both lipoprotein parameters correlate inversely with each other. Therefore, the etiological contributions of triglycerides and / or of HDL for developing cardiovascular disease can hardly be estimated from either observational studies or from intervention studies. The largely disappointing results of intervention studies with inhibitors of the cholesteryl ester transfer protein and in particular the available set of genetically-epidemiological studies suggest that in the last decade, the importance of HDL cholesterol has been overvalued, while the importance of triglycerides has been underestimated. High triglycerides not always atherogenic, but only if they are associated with the accumulation relatively cholesterol-enriched, incompletely catabolized remnants of chylomicrons and very low density lipoproteins (familial type III hyperlipidemia, metabolic syndrome, diabetes mellitus). The normalization of the concentration of triglycerides and remnants by inhibiting the expression of apolipoprotein C3 is hence a new, promising therapeutic target. PMID:27305303

  16. Lipoprotein metabolism in hypothyroidism : the contribution of growth hormone

    NARCIS (Netherlands)

    N. Hoogerbrugge (Nicoline)

    1992-01-01

    textabstractCurrent data suggest a role for GH in the regulation of lipoprotein metabolism. In hypothyroidism not only the secretion of thyroid hormone, but also of GH is decreased. Generally the effects on plasma lipids seen in hypothyroid individuals are considered to be a consequence of decreased

  17. Low-density lipoprotein cholesterol and risk of gallstone disease

    DEFF Research Database (Denmark)

    Stender, Stefan; Frikke-Schmidt, Ruth; Benn, Marianne;

    2013-01-01

    Drugs which reduce plasma low-density lipoprotein cholesterol (LDL-C) may protect against gallstone disease. Whether plasma levels of LDL-C per se predict risk of gallstone disease remains unclear. We tested the hypothesis that elevated LDL-C is a causal risk factor for symptomatic gallstone...

  18. Elevated Lipoprotein(A Impairs Platelet Radiolabeling Yield

    Directory of Open Access Journals (Sweden)

    Susanne Granegger

    2015-02-01

    Full Text Available Objectives: Platelet radiolabeling in clinical routine usually results in labeling efficiencies (LE above 80%. A variety of risk factors and clinical conditions are known to impair platelet labeling yield, among them elevated triglycerides and low-density lipoproteins. The potential influence of lipoprotein(a (Lp(a, an atherogenic lipoprotein particle containing a kringle subunit, which is widely found in the proteins of fibrinolysis pathway, has never been studied. Normal Lp(a levels range below 30 mg/ dl. The exact prevalence of elevated Lp(a is unknown, most likely ranging below 10%. Even more rare is an isolated elevation despite an otherwise normal lipoprotein profile. Methods: We examined the role of isolated elevated Lp(a (> 50 mg/dl, ranging up to 440 mg/dl compared to patients with normal lipid profile. Platelets were radiolabeled with in-111-oxine at 37 °C for 5 minutes using ISORBE-consensus methodology. Results: The findings indicate that already at levels below 100 mg/dl Lp(a decreases LE. LE assessment after cross-incubation of hyper-Lp(a platelets with normal Lp(a plasma and vice versa reveals that platelets rather than the plasmatic environment are responsible for the deterioration of labeling yield. This behavior already has been reported for elevated low-density lipoproteins. Apparently, the quantitative influence of LDL and Lp(a/mg is comparable. Plotting the sum of LDL and Lp(a versus LE reveals a clear significant negative correlation. Conclusion: As extremely elevated Lp(a, particularly above 150 mg/dl, may significantly impair labeling results. We therefore recommend to include extremely elevated Lp(a into the list of parameters, which should be known before performing radiolabeling of human platelets.

  19. On a New Species of Phyllodistomum Braun, 1899 (Digenea: Gorgoderidae, a Parasite of Fresh Water Fish, Channa Punctatus (Bl. from Betwa River, Bundelkhand Region Jhansi, U.P, India.

    Directory of Open Access Journals (Sweden)

    Jag Mohan Sen

    2014-04-01

    Full Text Available The present paper deals with a new species of genus Phyllodistum Braun, 1899. Phyllodistomum betwaensis sp.n. is reported from fresh water fish Channa punctatus (Bl. from Betwa river, Bundelkhand region,Jhansi. It differs from all the earlier reported species in having the body of fluke is spatulate and dorso-ventrally flattened; anterior portion of body is long and curved while posterior portion of body is broad; slightly curved, tubular oesophagus: ventral sucker oval and larger than oral sucker; testes, post-equatorial, inter-caecal, anterior testis is larger than posterior one and parallel to ovary; ovary, oval, just behind right vitelline lobe, parallel to anterior testis; vitelline lobes posterior-lateral to ventral sucker, oval. Right vitelline lobe is larger than left vitelline lobe; eggs are oval and non-operculated.

  20. Christina von Braun, Dorothea Dornhof, Eva Johach (Hg.: Das Unbewusste. Krisis und Kapital der Wissenschaften. Studien zum Verhältnis von Wissen und Geschlecht. Bielefeld: transcript Verlag 2009.

    Directory of Open Access Journals (Sweden)

    Zara Simone Pfeiffer

    2010-07-01

    Full Text Available Wissenschaft, die den Anspruch hat selbstreflexiv zu sein, sollte ihre unbewussten Anteile nicht ausblenden – das wird in den Beiträgen des von Christina von Braun, Dorothea Dornhof und Eva Johach herausgegebenen Sammelbandes auf überzeugende Weise gezeigt. Dabei geht es nicht primär um das Unbewusste als Objekt der Wissenschaften, sondern vielmehr um die Rolle des Unbewussten als Subjekt der Wissensordnung und Wissensproduktion, als „Krisis und Kapital“ der Wissenschaften, gleichermaßen als Sand und Öl imWissensgetriebe. Anstelle eines systematischen Überblicks liefert der interdisziplinär angelegte Band eine Vielzahl kluger, manchmal überraschender und durchgehend lesenswerter Perspektiven auf das visuelle und politische Unbewusste, seine Wissensgeschichte und seinen Ort in der Wissensordnung.Science, which purports to be self-reflexive, should not ignore its unconscious element – this is convincingly proven in the collected volume edited by Christina von Braun, Dorothea Dornhof, and Eva Johach. The focus is not merely on the unconscious as an object of the sciences, but on the role of the unconscious as a subject of knowledge organization and knowledge production, as “crisis and capital” of the sciences, indeed simultaneously functioning as sand and oil in the transmission of knowledge. In place of a systematic overview, the interdisciplinary volume offers a number of clever, sometimes surprising, and always well-worth reading perspectives on the visual and political unconscious, its history of knowledge, and its place in the order of knowledge.

  1. Deficiency of Lipoprotein Lipase in Neurons Decreases AMPA Receptor Phosphorylation and Leads to Neurobehavioral Abnormalities in Mice.

    Directory of Open Access Journals (Sweden)

    Tian Yu

    Full Text Available Alterations in lipid metabolism have been found in several neurodegenerative disorders, including Alzheimer's disease. Lipoprotein lipase (LPL hydrolyzes triacylglycerides in lipoproteins and regulates lipid metabolism in multiple organs and tissues, including the central nervous system (CNS. Though many brain regions express LPL, the functions of this lipase in the CNS remain largely unknown. We developed mice with neuron-specific LPL deficiency that became obese on chow by 16 wks in homozygous mutant mice (NEXLPL-/- and 10 mo in heterozygous mice (NEXLPL+/-. In the present study, we show that 21 mo NEXLPL+/- mice display substantial cognitive function decline including poorer learning and memory, and increased anxiety with no difference in general motor activities and exploratory behavior. These neurobehavioral abnormalities are associated with a reduction in the 2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl propanoic acid (AMPA receptor subunit GluA1 and its phosphorylation, without any alterations in amyloid β accumulation. Importantly, a marked deficit in omega-3 and omega-6 polyunsaturated fatty acids (PUFA in the hippocampus precedes the development of the neurobehavioral phenotype of NEXLPL+/- mice. And, a diet supplemented with n-3 PUFA can improve the learning and memory of NEXLPL+/- mice at both 10 mo and 21 mo of age. We interpret these findings to indicate that LPL regulates the availability of PUFA in the CNS and, this in turn, impacts the strength of synaptic plasticity in the brain of aging mice through the modification of AMPA receptor and its phosphorylation.

  2. Antagonism of Secreted PCSK9 Increases Low Density Lipoprotein Receptor Expression in HepG2 Cells

    Energy Technology Data Exchange (ETDEWEB)

    McNutt, Markey C.; Kwon, Hyock Joo; Chen, Chiyuan; Chen, Justin R.; Horton, Jay D.; Lagace, Thomas A.; (USMC); (UTSMC)

    2009-07-10

    PCSK9 is a secreted protein that degrades low density lipoprotein receptors (LDLRs) in liver by binding to the epidermal growth factor-like repeat A (EGF-A) domain of the LDLR. It is not known whether PCSK9 causes degradation of LDLRs within the secretory pathway or following secretion and reuptake via endocytosis. Here we show that a mutation in the LDLR EGF-A domain associated with familial hypercholesterolemia, H306Y, results in increased sensitivity to exogenous PCSK9-mediated cellular degradation because of enhanced PCSK9 binding affinity. The crystal structure of the PCSK9-EGF-A(H306Y) complex shows that Tyr-306 forms a hydrogen bond with Asp-374 in PCSK9 at neutral pH, which strengthens the interaction with PCSK9. To block secreted PCSK9 activity, LDLR (H306Y) subfragments were added to the medium of HepG2 cells stably overexpressing wild-type PCSK9 or gain-of-function PCSK9 mutants associated with hypercholesterolemia (D374Y or S127R). These subfragments blocked secreted PCSK9 binding to cell surface LDLRs and resulted in the recovery of LDLR levels to those of control cells. We conclude that PCSK9 acts primarily as a secreted factor to cause LDLR degradation. These studies support the concept that pharmacological inhibition of the PCSK9-LDLR interaction extracellularly will increase hepatic LDLR expression and lower plasma low density lipoprotein levels.

  3. Biological and virulence characteristics of the YqhC mutant of Salmonella.

    Science.gov (United States)

    Eakley, Nicholas M; Bochsler, Philip N; Gopal Reddy, P; Chopra, Ashok K; Fadl, Amin A

    2011-12-01

    Previous work by the present authors indicated a murein lipoprotein mutant of Salmonella shows a marked down-regulation in expression of yqhC. Because YqhC is a putative DNA-binding protein, it is likely involved in modulation of Salmonella genes. Deletion of yqhC renders Salmonella defective in invasion of intestinal epithelial cells, motility, and induction of cytotoxicity. In the present study, further attenuation in induction of inflammatory cytokines/chemokines and histopathological lesions was seen in mice infected with the yqhC mutant. On the other hand, deletion of yqhC did not significantly affect the LD(50) in mice or the ability of Salmonella to survive and replicate in vivo. To better understand how YqhC affects Salmonella virulence and to identify factors potentially modulated by YqhC, comparative transcriptome and proteome analysis of the yqhC mutant and the WT Salmonella was performed. Data from these experiments indicate that deletion of yqhC significantly alters the transcription of several genes associated with the SPI-1 encoded T3SS and flagellar regulons, correlating with the yqhC mutant phenotype. Overall, this study indicates that deletion of the yqhC gene causes a number of virulence-related defects in vitro, but has a modest effect in vivo, despite affecting induction of inflammatory cytokines and histopathology.

  4. Sorting of bacterial lipoproteins to the outer membrane by the Lol system.

    Science.gov (United States)

    Narita, Shin-ichiro; Tokuda, Hajime

    2010-01-01

    Bacterial lipoproteins comprise a subset of membrane proteins with a lipid-modified cysteine residue at their amino termini through which they are anchored to the membrane. In Gram-negative bacteria, lipoproteins are localized on either the inner or the outer membrane. The Lol system is responsible for the transport of lipoproteins to the outer membrane.The Lol system comprises an inner-membrane ABC transporter LolCDE complex, a periplasmic carrier protein, LolA, and an outer membrane receptor protein, LolB. Lipoproteins are synthesized as precursors in the cytosol and then translocated across the inner membrane by the Sec translocon to the outer leaflet of the inner membrane, where lipoprotein precursors are processed to mature lipoproteins. The LolCDE complex then mediates the release of outer membrane-specific lipoproteins from the inner membrane while the inner membrane-specific lipoproteins possessing Asp at position 2 are not released by LolCDE because it functions as a LolCDE avoidance signal, causing the retention of these lipoproteins in the inner membrane. A water-soluble lipoprotein-LolA complex is formed as a result of the release reaction mediated by LolCDE. This complex traverses the hydrophilic periplasm to reach the outer membrane, where LolB accepts a lipoprotein from LolA and then catalyzes its incorporation into the inner leaflet of the outer membrane. PMID:20419407

  5. Yeast mutants auxotrophic for choline or ethanolamine.

    OpenAIRE

    Atkinson, K D; Jensen, B.; Kolat, A I; Storm, E M; Henry, S. A.; Fogel, S

    1980-01-01

    Three mutants of the yeast Saccharomyces cerevisiae which require exogenous ethanolamine or choline were isolated. The mutants map to a single locus (cho1) on chromosome V. The lipid composition suggests that cho1 mutants do not synthesize phosphatidylserine under any growth conditions. If phosphatidylethanolamine or phosphatidylcholine, which are usually derived from phosphatidylserine, were synthesized from exogenous ethanolamine or choline, the mutants grew and divided relatively normally....

  6. Distinct Hepatic Receptors for Low Density Lipoprotein and Apolipoprotein E in Humans

    Science.gov (United States)

    Hoeg, Jeffrey M.; Demosky, Stephen J.; Gregg, Richard E.; Schaefer, Ernst J.; Brewer, H. Bryan

    1985-02-01

    Since the liver is a central organ for lipid and lipoprotein synthesis and catabolism, hepatic receptors for specific apolipoproteins on plasma lipoproteins would be expected to modulate lipid and lipoprotein metabolism. The role of hepatic receptors for low density lipoproteins and apolipoprotein E-containing lipoproteins was evaluated in patients with complementary disorders in lipoprotein metabolism: abetalipoproteinemia and homozygous familial hypercholesterolemia. In addition, hepatic membranes from a patient with familial hypercholesterolemia were studied and compared before and after portacaval shunt surgery. The results establish that the human liver has receptors for apolipoproteins B and E. Furthermore, in the human, hepatic receptors for low density lipoproteins and apolipoprotein E are genetically distinct and can undergo independent control.

  7. Reference serum protein and lipoprotein fractions of ostriches (Struthio camelus in Turkey : research communication

    Directory of Open Access Journals (Sweden)

    U. Polat

    2004-11-01

    Full Text Available The aim of this study was to determine for reference purposes the values of serum albumin, a1-globulin, a2-globulin, b-globulin, g-globulin, and a-lipoprotein (high density lipoprotein, pre-b-lipoprotein (very low density lipoprotein and b-lipoprotein (low density lipoprotein fractions of normal ostriches (Struthio camelus in Turkey. Five male and five female ostriches, 18 months old, were used. All the ostriches were fed on a diet that contained 15.14 % crude protein and 2 950 Kcal/kg of metabolizable energy. The serum protein and lipoprotein fractions were measured using agarose gel electrophoresis. The fractions were found to be 60.96 % albumin, 0.24% a1-globulin, 15.91 % a2-globulin, 13.34 % b-globulin, 9.55 % g-globulin, 53.77 % HDL, 0.60 % VLDL and 48.09 % LDL.

  8. Rapid characterization of disease-causing mutations in the low density lipoprotein receptor (LDL-R) gene by overexpression in COS cells

    DEFF Research Database (Denmark)

    Jensen, T G; Andresen, B S; Jensen, H K;

    1996-01-01

    surface is quantitated. The receptor activity is measured by incubating the cells with fluorescence labeled LDL (Dil-labelled LDL) at 37 degrees C and 4 degrees C. The transfected cells stained with anti-LDL-R antibodies can also be analysed by immunofluorescence microscopy allowing the study......To characterize disease-causing mutations in the low density lipoprotein receptor (LDL-R) gene, COS cells are transfected with the mutant gene in an EBV-based expression vector and characterized by flow cytometry. Using antibodies against the LDL-receptor the amount of receptor protein on the cell...... of the intracellular location of variants of the receptor. To evaluate these methods, we are analyzing four previously well-characterized LDL-R mutations, belonging to each of the classes 2 to 5. Preliminary data show that mutant genes belonging to class 3 and 4A give rise to receptor protein on the cell surface...

  9. Pharmacogenetic interaction between dexamethasone and Cd36-deficient segment of spontaneously hypertensive rat chromosome 4 affects triacylglycerol and cholesterol distribution into lipoprotein fractions.

    Science.gov (United States)

    Krupková, Michaela; Sedová, Lucie; Liska, Frantisek; Krenová, Drahomíra; Kren, Vladimír; Seda, Ondrej

    2010-04-16

    Dexamethasone (DEX) is known to induce diabetes and dyslipidemia. We have compared fasting triacylglycerol and cholesterol concentrations across 20 lipoprotein fractions and glucose tolerance in control (standard diet) and DEX-treated 7-month-old males of two rat strains, Brown Norway (BN) and congenic BN.SHR-(Il6-Cd36)/Cub (BN.SHR4). These two inbred strains differ in a defined segment of chromosome 4, originally transferred from the spontaneously hypertensive rat (SHR) including the mutant Cd36 gene, a known target of DEX. Compared to BN, the standard-diet-fed BN.SHR4 showed higher cholesterol and triacylglycerol concentrations across many lipoprotein fractions, particularly in small VLDL and LDL particles. Total cholesterol was decreased by DEX by more than 21% in BN.SHR4 contrasting with the tendency to increase in BN (strain*DEX interaction p = 0.0017). Similar pattern was observed for triacylglycerol concentrations in LDL. The LDL particle size was significantly reduced by DEX in both strains. Also, while control BN and BN.SHR4 displayed comparable glycaemic profiles during oral glucose tolerance test, we observed a markedly blunted DEX induction of glucose intolerance in BN.SHR4 compared to BN. In summary, we report a pharmacogenetic interaction between limited genomic segment with mutated Cd36 gene and dexamethasone-induced glucose intolerance and triacylglycerol and cholesterol redistribution into lipoprotein fractions.

  10. An extra early mutant of pigeonpea

    International Nuclear Information System (INIS)

    The redgram (Cajanus cajan (L.) Huth) variety 'Prabhat DT' was gamma irradiated with 100, 200, 300 and 400 Gy doses. Several mutants have been identified viz., extra early mutants, monostem mutants, obcordifoliate mutants and bi-stigmatic mutants. The extra early mutant was obtained when treated with 100 Gy dose. The mutant was selfed and forwarded from M2 to M4 generation. In the M4 generation the mutant line was raised along with the parental variety. Normal cultural practices were followed and the biometrical observations were recorded. It was observed that for the characters viz., total number of branches per plant, number of pods per plants, seeds per pod, 100 seed weight and seed yield per plant there was no difference between the mutant and parent variety. Whereas, regarding the days to flowering and maturity the mutants were earlier than the parents. The observation was recorded from two hundred plants each. The mutant gives the same yield in 90 days as that of the parent variety in 107 days, which make it an economic mutant

  11. Problem-Solving Test: Tryptophan Operon Mutants

    Science.gov (United States)

    Szeberenyi, Jozsef

    2010-01-01

    This paper presents a problem-solving test that deals with the regulation of the "trp" operon of "Escherichia coli." Two mutants of this operon are described: in mutant A, the operator region of the operon carries a point mutation so that it is unable to carry out its function; mutant B expresses a "trp" repressor protein unable to bind…

  12. Fluorescence correlation spectroscopy to measure the metabolism of high-density lipoprotein

    Science.gov (United States)

    Deitrick, Russell; Gibson, Emily; Razzaghi, Hamid

    2009-10-01

    High-density lipoprotein (HDL), referred to as the ``good cholesterol'', carries free cholesterol to the liver to be filtered from the bloodstream and is important to our understanding of atherosclerosis. HDL is metabolized in part by the enzyme Endothelial Lipase (EL). With this project we will use fluorescence correlation spectroscopy (FCS) to study the metabolism of HDL by EL comparing wild type with different genetic mutations. FCS is an advanced microscopy technique in which we record fluctuations in the fluorescence of dye-labeled molecules (in this case, HDL labeled with Nile Red) as they freely diffuse through a small focal volume. This data can be analyzed mathematically using the cross-correlation function, from which we can ultimately ascertain much information. In our case, we are interested in the diffusion coefficient which, via the Stokes-Einstein relation for a sphere, we can determine the size of HDL as it undergoes the process of metabolism. Preliminary results seem to indicate that the metabolic process occurs very quickly, that the final size of HDL depends primarily on the concentration of EL, and that the wild and mutant variants of EL have a similar effectiveness. In following experiments, we hope to investigate these relationships further.

  13. Familial defective apolipoprotein B-100: low density lipoproteins with abnormal receptor binding

    International Nuclear Information System (INIS)

    Previous in vivo turnover studies suggested that retarded clearance of low density lipoproteins (LDL) from the plasma of some hypercholesterolemic patients is due to LDL with defective receptor binding. The present study examined this postulate directly by receptor binding experiments. The LDL from a hypercholesterolemic patient (G.R.) displayed a reduced ability to bind to the LDL receptors on normal human fibroblasts. The G.R. LDL possessed 32% of normal receptor binding activity. Likewise, the G.R. LDL were much less effective than normal LDL in competing with 125I-labeled normal LDL for cellular uptake and degradation and in stimulating intracellular cholesteryl ester synthesis. The defect in LDL binding appears to be due to a genetic abnormality of apolipoprotein B-100: two brothers of the proband possess LDL defective in receptor binding, whereas a third brother and the proband's son have normally binding LDL. Further, the defect in receptor binding does not appear to be associated wit an abnormal lipid composition or structure of the LDL. Normal and abnormal LDL subpopulations were partially separated from plasma of two subjects by density-gradient ultracentrifugation, a finding consistent with the presence of a normal and a mutant allele. The affected family members appear to be heterozygous for this disorder, which has been designated familial defective apolipoprotein B-100. These studies indicate that the defective receptor binding results in inefficient clearance of LDL and the hypercholesterolemia observed in these patients

  14. High-density lipoprotein is a potential growth factor for adrenocortical cells

    International Nuclear Information System (INIS)

    The entry of cholesterol contained within high-density lipoprotein (HDL) into adrenocortical cells is mediated by a human homologue of SR-BI, CD36, and LIMPII Analogous-1 (CLA-1) and thus augmenting their growth. To address the role of CLA-1, we created a mutant mCLA that lacked the C-terminal tail. HDL CE selective uptake by cells carrying the mCLA-1 receptor was fully active and equivalent to those transfected with full-length CLA-1 (fCLA-1). Expression of mCLA inhibited the proliferation of an adrenocortical cell line and the incorporation of [3H]thymidine into the cells. This effect was sensitive to wortmannin, an inhibitor of phosphoinositide 3-kinase (PI3K). Our transcriptional studies revealed that the inhibitory action of mCLA required the transcriptional factor AP-1 and the effect of HDL on AP-1 activation was also abrogated by wortmannin. These findings raise the possibility that the inhibitors of the effects of HDL may be of therapeutic value for adrenocortical tumor

  15. Cholesterol pathways affected by small molecules that decrease sterol levels in Niemann-Pick type C mutant cells.

    Directory of Open Access Journals (Sweden)

    Madalina Rujoi

    Full Text Available BACKGROUND: Niemann-Pick type C (NPC disease is a genetically inherited multi-lipid storage disorder with impaired efflux of cholesterol from lysosomal storage organelles. METHODOLOGY/PRINCIPAL FINDINGS: The effect of screen-selected cholesterol lowering compounds on the major sterol pathways was studied in CT60 mutant CHO cells lacking NPC1 protein. Each of the selected chemicals decreases cholesterol in the lysosomal storage organelles of NPC1 mutant cells through one or more of the following mechanisms: increased cholesterol efflux from the cell, decreased uptake of low-density lipoproteins, and/or increased levels of cholesteryl esters. Several chemicals promote efflux of cholesterol to extracellular acceptors in both non-NPC and NPC1 mutant cells. The uptake of low-density lipoprotein-derived cholesterol is inhibited by some of the studied compounds. CONCLUSIONS/SIGNIFICANCE: Results herein provide the information for prioritized further studies in identifying molecular targets of the chemicals. This approach proved successful in the identification of seven chemicals as novel inhibitors of lysosomal acid lipase (Rosenbaum et al, Biochim. Biophys. Acta. 2009, 1791:1155-1165.

  16. Oxidized low-density lipoprotein in postmenopausal women

    DEFF Research Database (Denmark)

    Jankowski, Vera; Just, Alexander R; Pfeilschifter, Johannes;

    2014-01-01

    of this study was to determine the prevalence of serum oxLDL in postmenopausal women and to identify possible associations of clinical and laboratory features with oxLDL in these patients. METHOD: After clinical examination and completing a clinical questionnaire, an ultrasound examination of both carotid.......10-0.43). Although intima-media thickness did not differ, postmenopausal women with serous oxLDL had more often atherosclerotic plaques compared to women without oxLDL (6/66 vs. 0/467; P high-density lipoprotein, impaired glucose intolerance, and DBP were independently associated...... with the occurrence of oxLDL. If oxLDL was present, higher high-density lipoprotein and glucose intolerance were associated with higher concentrations of oxLDL. In contrast, higher blood urea concentrations were associated with lower concentrations of oxLDL. CONCLUSION: This study presents the prevalence...

  17. Recombinant human LCAT normalizes plasma lipoprotein profile in LCAT deficiency.

    Science.gov (United States)

    Simonelli, Sara; Tinti, Cristina; Salvini, Laura; Tinti, Laura; Ossoli, Alice; Vitali, Cecilia; Sousa, Vitor; Orsini, Gaetano; Nolli, Maria Luisa; Franceschini, Guido; Calabresi, Laura

    2013-11-01

    Lecithin:cholesterol acyltransferase (LCAT) is the enzyme responsible for cholesterol esterification in plasma. Mutations in the LCAT gene leads to two rare disorders, familial LCAT deficiency and fish-eye disease, both characterized by severe hypoalphalipoproteinemia associated with several lipoprotein abnormalities. No specific treatment is presently available for genetic LCAT deficiency. In the present study, recombinant human LCAT was expressed and tested for its ability to correct the lipoprotein profile in LCAT deficient plasma. The results show that rhLCAT efficiently reduces the amount of unesterified cholesterol (-30%) and promotes the production of plasma cholesteryl esters (+210%) in LCAT deficient plasma. rhLCAT induces a marked increase in HDL-C levels (+89%) and induces the maturation of small preβ-HDL into alpha-migrating particles. Moreover, the abnormal phospholipid-rich particles migrating in the LDL region were converted in normally sized LDL.

  18. [Various lipoprotein fractions and their relation to ischemic heart disease].

    Science.gov (United States)

    Palazzuoli, V; Mondillo, S; Kristodhullu, A; De Stefano, R; Amatucci, G

    1983-01-01

    In a study carried out on over 700 patients with three different manifestations of aterosclerosis (cerebrovascular, coronary and peripheral), we could not find any statistically significant difference between the total cholesterol and triglyceride concentration in these three groups. Also, there was o difference in cholesterol and triglyceride levels between these three groups and 200 normal subjects. The same held true when we compared a selected group of 76 patients with ischaemic heart disease who had no other risk factor, with a group of 80 control subjects. On the contrary, when we compared several fractions of serum lipoproteins and the ratios of apolipoprotein A to Apolipoprotein B, LDL Cholesterol to HDL Cholesterol, and total Cholesterol to HDL Cholesterol of the two groups, the differences were statistically significant. We conclude that when other risk factors are excluded, the protein component, rather than the lipid component of the plasma lipoproteins correlates the presence of coronary artery disease.

  19. Lipoprotein Metabolism and Inflammation in Patients With Psoriasis.

    Science.gov (United States)

    Armstrong, Ehrin J; Krueger, James G

    2016-08-15

    Psoriasis is a chronic inflammatory disease associated with a variety of co-morbid conditions, including cardiovascular disease. Advancements in our understanding of the cellular and molecular mechanisms of psoriasis have led to a better understanding regarding its pathogenesis, which in turn has stimulated ongoing research to identify the underlying pathophysiology responsible for the increased risk of cardiovascular events associated with psoriasis. Although not yet fully elucidated, emerging evidence points to immune-mediated inflammation as a process that contributes to endothelial cell dysfunction, dyslipidemia, and atherosclerosis as key processes influencing cardiovascular disease in psoriasis. In particular, the dyslipidemia present in psoriasis may be associated with altered lipoprotein function and increased atherogenicity. Here, we review how the cytokine networks involved in lipoprotein metabolism and inflammation could impact on the cardiovascular disease risk for patients with psoriasis. PMID:27392508

  20. A clustering analysis of lipoprotein diameters in the metabolic syndrome

    Directory of Open Access Journals (Sweden)

    Frazier-Wood Alexis C

    2011-12-01

    Full Text Available Abstract Background The presence of smaller low-density lipoproteins (LDL has been associated with atherosclerosis risk, and the insulin resistance (IR underlying the metabolic syndrome (MetS. In addition, some research has supported the association of very low-, low- and high-density lipoprotein (VLDL HDL particle diameters with components of the metabolic syndrome (MetS, although this has been the focus of less research. We aimed to explore the relationship of VLDL, LDL and HDL diameters to MetS and its features, and by clustering individuals by their diameters of VLDL, LDL and HDL particles, to capture information across all three fractions of lipoprotein into a unified phenotype. Methods We used nuclear magnetic resonance spectroscopy measurements on fasting plasma samples from a general population sample of 1,036 adults (mean ± SD, 48.8 ± 16.2 y of age. Using latent class analysis, the sample was grouped by the diameter of their fasting lipoproteins, and mixed effects models tested whether the distribution of MetS components varied across the groups. Results Eight discrete groups were identified. Two groups (N = 251 were enriched with individuals meeting criteria for the MetS, and were characterized by the smallest LDL/HDL diameters. One of those two groups, one was additionally distinguished by large VLDL, and had significantly higher blood pressure, fasting glucose, triglycerides, and waist circumference (WC; P Conclusions While small LDL diameters remain associated with IR and the MetS, the occurrence of these in conjunction with a shift to overall larger VLDL diameter may identify those with the highest fasting glucose, TG and WC within the MetS. If replicated, the association of this phenotype with more severe IR-features indicated that it may contribute to identifying of those most at risk for incident type II diabetes and cardiometabolic disease.

  1. Transgenic rabbit that expresses a functional human lipoprotein (a)

    Science.gov (United States)

    Rouy, Didier; Duverger, Nicolas; Emmanuel, Florence; Denefle, Patrice; Houdebine, Louis-Marie; Viglietta, Celine; Rubin, Edward M.; Hughes, Steven D.

    2003-01-01

    A transgenic rabbit which has in its genomic DNA sequences that encode apolipoprotein (a) and apolipoprotein B polypeptides which are capable of combining to produce lipoprotein (a), a process for creating such a rabbit, and the use of the rabbit to identify compounds which are effective in the treatment of human diseases which are associated with, induced and/or exacerbated by Lp(a) expression.

  2. Lipoprotein metabolism in hypothyroidism : the contribution of growth hormone

    OpenAIRE

    Hoogerbrugge, Nicoline

    1992-01-01

    textabstractCurrent data suggest a role for GH in the regulation of lipoprotein metabolism. In hypothyroidism not only the secretion of thyroid hormone, but also of GH is decreased. Generally the effects on plasma lipids seen in hypothyroid individuals are considered to be a consequence of decreased thyroid hormone levels. More then twenty years ago evidence was found that treatment of hypothyroid rats with GH in supraphysiologic doses affects plasma lipid concentrations, but whether a lack o...

  3. Role of lipids in spheroidal high density lipoproteins

    OpenAIRE

    Timo Vuorela; Andrea Catte; Niemelä, Perttu S.; Anette Hall; Marja T Hyvönen; Siewert-Jan Marrink; Mikko Karttunen; Ilpo Vattulainen

    2010-01-01

    We study the structure and dynamics of spherical high density lipoprotein (HDL) particles through coarse-grained multi-microsecond molecular dynamics simulations. We simulate both a lipid droplet without the apolipoprotein A-I (apoA-I) and the full HDL particle including two apoA-I molecules surrounding the lipid compartment. The present models are the first ones among computational studies where the size and lipid composition of HDL are realistic, corresponding to human serum HDL. We focus o...

  4. Role of Lipids in Spheroidal High Density Lipoproteins

    OpenAIRE

    Vuorela, Timo; Catte, Andrea; Niemela, Perttu S.; Hall, Anette; Hyvonen, Marja T.; Marrink, Siewert-Jan; Karttunen, Mikko; Vattulainen, Ilpo; Niemelä, Perttu S.; Marja T Hyvönen

    2010-01-01

    We study the structure and dynamics of spherical high density lipoprotein (HDL) particles through coarse-grained multi-microsecond molecular dynamics simulations. We simulate both a lipid droplet without the apolipoprotein A-I (apoA-I) and the full HDL particle including two apoA-I molecules surrounding the lipid compartment. The present models are the first ones among computational studies where the size and lipid composition of HDL are realistic, corresponding to human serum HDL. We focus o...

  5. Role of Triglyceride-rich Lipoproteins in Renal Injury

    OpenAIRE

    Ng, Kit Fai; AUNG, HNIN HNIN; Rutledge, John C.

    2011-01-01

    Dyslipidemia is implicated as a risk factor for the development of atherosclerosis. Specifically triglyceride-rich lipoproteins (TGRL) and their lipolysis products are shown to be pro-inflammatory and pro-apoptosis in both in vivo and in vitro studies with endothelium. However the role of TGRL in the progression of kidney diseases is not clear. Epidemiology studies demonstrated a correlation between renal disease and blood lipids. Recent evidence suggests that the mechanism may involve cellul...

  6. Lipoprotein lipase is produced, regulated, and functional in rat brain.

    OpenAIRE

    Eckel, R.H.; Robbins, R J

    1984-01-01

    Lipoprotein lipase (LP lipase, triacylglycero-protein acylhydrolase EC 3.1.1.34) activity was found in four dissimilar brain regions (hypothalamus, cortex, cerebellum, and midbrain) of adult male rats. Progressive accumulation of LP lipase activity in cultured fetal rat hypothalamic cells was also observed, indicating de novo synthesis of the lipase. The brain LP lipase activity was serum-dependent and was inhibited by 1 M NaCl and by protamine sulfate. Kinetic analysis revealed an apparent K...

  7. Methods for studying rodent intestinal lipoprotein production and metabolism

    OpenAIRE

    Kohan, Alison B.; HOWLES, PHILIP N.; Tso, Patrick

    2012-01-01

    Lipid absorption begins with the digestion of dietary triacylglycerol and ultimately results in the secretion of triacylglycerol in chylomicrons into the lymphatics. Additionally, the intestine also secretes numerous proteins and peptides involved in lipid and lipoprotein metabolism in response to food. Ultimately, chylomicrons and these proteins, peptides, and hormones are found in lymph. The lymph fistula rat model has traditionally been used to study this intestinal absorption of nutrients...

  8. Lipoprotein(a Serum Levels in Diabetic Patients with Retinopathy

    Directory of Open Access Journals (Sweden)

    Giulia Malaguarnera

    2013-01-01

    Full Text Available Background. Atherogenic lipoproteins, such as total cholesterol, LDL cholesterol, oxidized low density lipoprotein, and triglycerides, are associated with progression of retinopathy. Aim. To evaluate the relationship between lipoprotein(a and retinopathy in patients with type 2 diabetes mellitus. Materials and Methods. We enrolled 145 diabetic consecutive patients (82 females, 63 males; mean age 66.8±12 years, mean duration of diabetes 9.4±6.8 years. Presence and severity of retinopathy were evaluated. Serum lipid profile, including Lp(a level, was assessed. Results. High Lp(a levels have been observed in 54 (78.3% subjects and normal levels in 13 (18.85% subjects as regards diabetic patients with retinopathy. Lp(a levels were high in 15 subjects (21.75% and normal in 63 subjects (91.35% as regards patients without retinopathy. Conclusions. Lp(a levels are increased in a significant percentage of patients with retinopathy compared to diabetic patients without retinopathy. The impact of Lp(a levels on diabetic retinopathy needs to be further investigated.

  9. Triglyceride-Rich Lipoproteins and Remnants: Targets for Therapy?

    Science.gov (United States)

    Dallinga-Thie, Geesje M; Kroon, Jeffrey; Borén, Jan; Chapman, M John

    2016-07-01

    It is now evident that elevated circulating levels of triglycerides in the non-fasting state, a marker for triglyceride (TG)-rich remnant particles, are associated with increased risk of premature cardiovascular disease (CVD). Recent findings from basic and clinical studies have begun to elucidate the mechanisms that contribute to the atherogenicity of these apoB-containing particles. Here, we review current knowledge of the formation, intravascular remodelling and catabolism of TG-rich lipoproteins and highlight (i) the pivotal players involved in this process, including lipoprotein lipase, glycosylphosphatidylinositol HDL binding protein 1 (GPIHBP1), apolipoprotein (apo) C-II, apoC-III, angiopoietin-like protein (ANGPTL) 3, 4 and 8, apoA-V and cholesteryl ester transfer protein; (ii) key determinants of triglyceride (TG) levels and notably rates of production of very-low-density lipoprotein 1 (VLDL1) particles; and (iii) the mechanisms which underlie the atherogenicity of remnant particles. Finally, we emphasise the polygenic nature of moderate hypertriglyceridemia and briefly discuss modalities for its clinical management. Several new therapeutic strategies to attenuate hypertriglyceridemia have appeared recently, among which those targeted to apoC-III appear to hold considerable promise. PMID:27216847

  10. Triglyceride-rich lipoproteins and high-density lipoprotein cholesterol in patients at high risk of cardiovascular disease: evidence and guidance for management

    DEFF Research Database (Denmark)

    Chapman, M John; Ginsberg, Henry N; Amarenco, Pierre;

    2011-01-01

    Even at low-density lipoprotein cholesterol (LDL-C) goal, patients with cardiometabolic abnormalities remain at high risk of cardiovascular events. This paper aims (i) to critically appraise evidence for elevated levels of triglyceride-rich lipoproteins (TRLs) and low levels of high...

  11. Triglyceride-rich lipoproteins and high-density lipoprotein cholesterol in patients at high risk of cardiovascular disease: evidence and guidance for management

    DEFF Research Database (Denmark)

    Chapman, M John; Ginsberg, Henry N; Amarenco, Pierre;

    2011-01-01

    Even at low-density lipoprotein cholesterol (LDL-C) goal, patients with cardiometabolic abnormalities remain at high risk of cardiovascular events. This paper aims (i) to critically appraise evidence for elevated levels of triglyceride-rich lipoproteins (TRLs) and low levels of high-density lipop...

  12. Low-Density Lipoprotein Receptor-Related Protein 6 (LRP6 Is a Novel Nutritional Therapeutic Target for Hyperlipidemia, Non-Alcoholic Fatty Liver Disease, and Atherosclerosis

    Directory of Open Access Journals (Sweden)

    Gwang-woong Go

    2015-06-01

    Full Text Available Low-density lipoprotein receptor-related protein 6 (LRP6 is a member of the low-density lipoprotein receptor family and has a unique structure, which facilitates its multiple functions as a co-receptor for Wnt/β-catenin signaling and as a ligand receptor for endocytosis. The role LRP6 plays in metabolic regulation, specifically in the nutrient-sensing pathway, has recently garnered considerable interest. Patients carrying an LRP6 mutation exhibit elevated levels of LDL cholesterol, triglycerides, and fasting glucose, which cooperatively constitute the risk factors of metabolic syndrome and atherosclerosis. Since the discovery of this mutation, the general role of LRP6 in lipid homeostasis, glucose metabolism, and atherosclerosis has been thoroughly researched. These studies have demonstrated that LRP6 plays a role in LDL receptor-mediated LDL uptake. In addition, when the LRP6 mutant impaired Wnt-LRP6 signaling, hyperlipidemia, non-alcoholic fatty liver disease, and atherosclerosis developed. LRP6 regulates lipid homeostasis and body fat mass via the nutrient-sensing mechanistic target of the rapamycin (mTOR pathway. Furthermore, the mutant LRP6 triggers atherosclerosis by activating platelet-derived growth factor (PDGF-dependent vascular smooth muscle cell differentiation. This review highlights the exceptional opportunities to study the pathophysiologic contributions of LRP6 to metabolic syndrome and cardiovascular diseases, which implicate LRP6 as a latent regulator of lipid metabolism and a novel therapeutic target for nutritional intervention.

  13. Induction of Experimental Arthritis by Borrelial Lipoprotein and CpG Motifs: Are Toll-Like Receptors 2, 4, 9 or CD-14 Involved?

    Energy Technology Data Exchange (ETDEWEB)

    Batsford, S.; Dunn, J.; Mihatsch, M.

    2011-06-01

    Bacterial lipoproteins and CpG-DNA are ligands for Toll-Like-Receptors (TLR) 2 and 9 respectively. Both classes of molecules were reported to induce experimental arthritis in rodents following direct intra-articular injection. Here we studied: (1) whether arthritis induction by Outer surface (Lipo)protein A (OspA) (B.burgdorferi) involved the TLR-2 as well as the TLR-4 or the CD-14 receptors in addition, and (2) re-examined the arthritogenic potential of CpG-DNA motifs in mice. Following intra-articular injection of the test substances [20 {micro}g recombinant, lipidated OspA; 1nM(6 {micro}g) to 10nM(60 {micro}g) synthetic CpG-DNA], inflammation was monitored by {sup 99}Tc scintigraphy (ratio left/right knee joint uptake > 1.1 indicates inflammation) and by histology. Lipoprotein OspA induced severe, acute arthritis in TLR-2{sup +/+} w.t. but not in TLR-2{sup -/-} mice (p<0.01). There were no significant differences in the severity of arthritis induced in TLR-4{sup +/+} w.t. and TLR-4{sup -/-} mutant mice, or between CD14{sup +/+} w.t. and CD14{sup -/-} mice. CpG-DNA (1or 10 nM) did not cause notable inflammation in C57BL/6 mice; {sup 99}Tc ratios were < 1.0 and histology showed only minimal changes. Induction of arthritis by the OspA lipoprotein of B.burgdorferi involves the TLR-2 receptor, no evidence for additional participation of TLR-4 or CD14 receptors was found. Intra-articular injection of CpG-DNA did not produce manifest joint injury in mice, at variance with previous reports.

  14. Androgen and FSH synergistically stimulate lipoprotein degradation and utilization by ovary granulosa cells

    International Nuclear Information System (INIS)

    Androgen can directly modulate the induction of steroidogenic enzymes by FSH (follicle stimulating hormone) in ovary granulosa cells. In studies of its mechanism of action, the authors examined the androgen effect on granulosa cell interaction with lipoproteins, the physiologic source of cholesterol. After granulosa cells were cultured for 48 hours with and without androgen and/or FSH, the cells were incubated for 24 hours with 125I-lipoproteins [human high density lipoprotein (HDL), rat HDL, or human low density lipoprotein (LDL)]. The media were then analyzed for lipoprotein protein coat degradation products (mainly 125I-monoiodotyrosine) and progestin [mainly 20 alpha-dihydroprogesterone (20 alpha-DHP)]. In the absence of FSH and androgen, 2 X 10(5) granulosa cells degraded basal levels of all three lipoproteins, but produced no measurable 20 alpha-DHP. The addition of 10(-7) M androstenedione (A), testosterone (T), or 5 alpha-dihydrotestosterone (DHT) had no effect on lipoprotein protein degradation or 20 alpha-DHP production. FSH alone stimulated lipoprotein protein degradation by 50 to 300% while the addition of androgen synergistically augmented the FSH-stimulated 20 alpha-DHP production as well as protein coat degradation of all three lipoproteins. DHT and T were both effective, indicating that androgens themselves, and not estrogen products, were responsible for the effect on lipoprotein protein degradation and 20 alpha-DHP production

  15. The membrane bound LRR lipoprotein Slr, and the cell wall-anchored M1 protein from Streptococcus pyogenes both interact with type I collagen.

    Directory of Open Access Journals (Sweden)

    Marta Bober

    Full Text Available Streptococcus pyogenes is an important human pathogen and surface structures allow it to adhere to, colonize and invade the human host. Proteins containing leucine rich repeats (LRR have been identified in mammals, viruses, archaea and several bacterial species. The LRRs are often involved in protein-protein interaction, are typically 20-30 amino acids long and the defining feature of the LRR motif is an 11-residue sequence LxxLxLxxNxL (x being any amino acid. The streptococcal leucine rich (Slr protein is a hypothetical lipoprotein that has been shown to be involved in virulence, but at present no ligands for Slr have been identified. We could establish that Slr is a membrane attached horseshoe shaped lipoprotein by homology modeling, signal peptidase II inhibition, electron microscopy (of bacteria and purified protein and immunoblotting. Based on our previous knowledge of LRR proteins we hypothesized that Slr could mediate binding to collagen. We could show by surface plasmon resonance that recombinant Slr and purified M1 protein bind with high affinity to collagen I. Isogenic slr mutant strain (MB1 and emm1 mutant strain (MC25 had reduced binding to collagen type I as shown by slot blot and surface plasmon resonance. Electron microscopy using gold labeled Slr showed multiple binding sites to collagen I, both to the monomeric and the fibrillar structure, and most binding occurred in the overlap region of the collagen I fibril. In conclusion, we show that Slr is an abundant membrane bound lipoprotein that is co-expressed on the surface with M1, and that both these proteins are involved in recruiting collagen type I to the bacterial surface. This underlines the importance of S. pyogenes interaction with extracellular matrix molecules, especially since both Slr and M1 have been shown to be virulence factors.

  16. Lipoprotein ratios: Physiological significance and clinical usefulness in cardiovascular prevention

    Directory of Open Access Journals (Sweden)

    Jesús Millán

    2009-09-01

    Full Text Available Jesús Millán1, Xavier Pintó2, Anna Muñoz3, Manuel Zúñiga4, Joan Rubiés-Prat5, Luis Felipe Pallardo6, Luis Masana7, Alipio Mangas8, Antonio Hernández-Mijares9, Pedro González-Santos10, Juan F Ascaso11, Juan Pedro-Botet121Hospital Universitario Gregorio Marañón, Madrid, Spain; 2Hospital Universitario Bellvitge, L’Hospitalet de Llobregat, Barcelona, Spain; 3Solvay Pharma, Barcelona, Spain; 4Hospital Marqués de Valdecilla, Santander, Spain; 5Hospital Vall d’Hebrón, Barcelona, Spain; 6Hospital Universitario La Paz, Madrid, Spain; 7Hospital Sant Joan, Reus, Tarragona, Spain; 8Hospital Universitario Puerta del Mar, Cádiz, Spain; 9Hospital Universitario Dr Peset, Valencia, Spain; 10Hospital Clínico Universitario Virgen de la Victoria, Málaga, Spain; 11Hospital Clínico Universitario, Valencia, Spain; 12Hospital del Mar, Barcelona, SpainAbstract: Low-density lipoprotein (LDL cholesterol concentration has been the prime index of cardiovascular disease risk and the main target for therapy. However, several lipoprotein ratios or “atherogenic indices” have been defined in an attempt to optimize the predictive capacity of the lipid profile. In this review, we summarize their pathophysiological aspects, and highlight the rationale for using these lipoprotein ratios as cardiovascular risk factors in clinical practice, specifying their cut-off risk levels and a target for lipid-lowering therapy. Total/high-density lipoprotein (HDL cholesterol and LDL/HDL cholesterol ratios are risk indicators with greater predictive value than isolated parameters used independently, particularly LDL. Future recommendations regarding the diagnosis and treatment of dyslipidemia, including instruments for calculating cardiovascular risk or action guidelines, should include the lipoprotein ratios with greater predictive power which, in view of the evidence-based results, are none other than those which include HDL cholesterol.Keywords: apolipoproteins

  17. Sorting of an integral outer membrane protein via the lipoprotein-specific Lol pathway and a dedicated lipoprotein pilotin.

    Science.gov (United States)

    Collin, Séverine; Guilvout, Ingrid; Nickerson, Nicholas N; Pugsley, Anthony P

    2011-05-01

    The lipoprotein PulS is a dedicated chaperone that is required to target the secretin PulD to the outer membrane in Klebsiella or Escherichia coli, and to protect it from proteolysis. Here, we present indirect evidence that PulD protomers do not assemble into the secretin dodecamer before they reach the outer membrane, and that PulS reaches the outer membrane in a soluble heterodimer with the general lipoprotein chaperone LolA. However, we could not find any direct evidence for PulD protomer association with the PulS-LolA heterodimer. Instead, in cells producing PulD and a permanently locked PulS-LolA dimer (in which LolA carries an R43L substitution that prevents lipoprotein transfer to LolB in the outer membrane), LolAR43L was found in the inner membrane, probably still associated with PulS bound to PulD that had been incorrectly targeted because of the LolAR43L substitution. It is speculated that PulD protomers normally cross the periplasm together with PulS bound to LolA but when the latter cannot be separated (due to the mutation in lolA), the PulD protomers form dodecamers that insert into the inner membrane. PMID:21338419

  18. Gamma ray induced mutants in Coleus

    International Nuclear Information System (INIS)

    The germplasm collection of Chinese potato (Coleus parviflorus Benth) contains almost no variation for yield contributing traits. The crop does not produce seeds. Treatment of underground tubers with 1 kR, 2 kR, 3 kR and 4 kR gamma rays resulted in 50 morphologically different mutants which are maintained as mutant clones. In the M1V1 generation, suspected mutant sprouts, were carefully removed and grown separately. The most interesting mutant types are the following: (i) erect mutant with spoon shaped light green leaves, 30 cm long inflorescences against 20 cm in the control, cylindrical tubers measuring ca. 7.0 cm long and 3 cm girth against 4 cm and 2.5 cm in the control (ii) early mutants 1 and 2, one having less leaf serration, the other having light green small leaves and dwarf type (iii) fleshy leaf mutant, dark green, thick and smooth leaves. Control plants spread almost in 1 m2 area and bear tubers from the nodes of branches. In the early mutants tuber formation is mainly restricted to the base of the plant, which makes harvest easier. The crop usually matures within 150 - 160 days, the early mutants are ready for harvest 100 days after planting. As the mutants are less spreading, the yield could be increased by closer spacing

  19. Lipoprotein N-acyl transferase (Lnt1) is dispensable for protein O-mannosylation by Streptomyces coelicolor.

    Science.gov (United States)

    Córdova-Dávalos, Laura Elena; Espitia, Clara; González-Cerón, Gabriela; Arreguín-Espinosa, Roberto; Soberón-Chávez, Gloria; Servín-González, Luis

    2014-01-01

    A protein glycosylation system related to that for protein mannosylation in yeast is present in many actinomycetes. This system involves polyprenyl phosphate mannose synthase (Ppm), protein mannosyl transferase (Pmt), and lipoprotein N-acyl transferase (Lnt). In this study, we obtained a series of mutants in the ppm (sco1423), lnt1 (sco1014), and pmt (sco3154) genes of Streptomyces coelicolor, which encode Ppm, Lnt1, and Pmt, to analyze their requirement for glycosylation of the heterologously expressed Apa glycoprotein of Mycobacterium tuberculosis. The results show that both Ppm and Pmt were required for Apa glycosylation, but that Lnt1 was dispensable for both Apa and the bacteriophage φC31 receptor glycosylation. A bacterial two-hybrid assay revealed that contrary to M. tuberculosis, Lnt1 of S. coelicolor does not interact with Ppm. The D2 catalytic domain of M. tuberculosisPpm was sufficient for complementation of an S. coelicolor double mutant lacking Lnt1 and Ppm, both for Apa glycosylation and for glycosylation of φC31 receptor. On the other hand, M. tuberculosisPmt was not active in S. coelicolor, even when correctly localized to the cytoplasmic membrane, showing fundamental differences in the requirements for Pmt activity in these two species.

  20. Small-Molecule Inhibitors of Gram-Negative Lipoprotein Trafficking Discovered by Phenotypic Screening

    OpenAIRE

    McLeod, Sarah M.; Fleming, Paul R.; MacCormack, Kathleen; McLaughlin, Robert E.; Whiteaker, James D.; Narita, Shin-ichiro; Mori, Makiko; Tokuda, Hajime; Miller, Alita A.

    2015-01-01

    In Gram-negative bacteria, lipoproteins are transported to the outer membrane by the Lol system. In this process, lipoproteins are released from the inner membrane by the ABC transporter LolCDE and passed to LolA, a diffusible periplasmic molecular chaperone. Lipoproteins are then transferred to the outer membrane receptor protein, LolB, for insertion in the outer membrane. Here we describe the discovery and characterization of novel pyridineimidazole compounds that inhibit this process. Esch...

  1. Effect of cobalt chloride on content of lipids and lipoproteins in serum and liver of rats.

    Science.gov (United States)

    Kaliman, P A; Shalamov, R V; Zagaiko, A L

    1997-07-01

    Lipids and the composition of lipoproteins in blood serum and liver cytosol, total lipid, and phospholipid contents in liver subcellular fractions and the spectrum of microsomal liver lipids were studied in male Wistar rats after a single injection of cobalt chloride. Virtually all lipid and lipoprotein fractions in blood and liver were increased and lipoprotein composition was changes. The lipid composition of liver microsomes did not change under these conditions. Thus, microsomal membranes are stable under developing oxidative stress. PMID:9331964

  2. Hormone-induced rearrangement of locust haemolymph lipoproteins The involvement of glycoprotein C2

    OpenAIRE

    Van der Horst, D J; Doorn, J.M. van; Beenakkers, A.M.Th.

    1984-01-01

    Formation of lipoprotein A⁺ and elevation of lipoprotein fraction O in locust (Locusta migratoria migratorioides) haemolymph as induced by adipokinetic hormone (AKH) includes the participation of non-lipid carrying proteins (fraction C), which was examined in more detail. By using gel filtration chromatography, the rather heterogenous C-proteins were resolved into three protein fractions, only one of which (C₂) appeared to be actually involved in the lipoprotein reassociation. The changes in ...

  3. Imaging of hepatic low density lipoprotein receptors by radionuclide scintiscanning in vivo.

    OpenAIRE

    Huettinger, M; Corbett, J R; Schneider, W J; Willerson, J T; Brown, M S; Goldstein, J L

    1984-01-01

    The low density lipoprotein (LDL) receptor mediates the cellular uptake of plasma lipoproteins that are derived from very low density lipoproteins (VLDL). Most of the functional LDL receptors in the body are located in the liver. Here, we describe a radionuclide scintiscanning technique that permits the measurement of LDL receptors in the livers of intact rabbits. 123I-labeled VLDL were administered intravenously, and scintigraphic images of the liver and heart were obtained at intervals ther...

  4. The lipoprotein lipase gene in combined hyperlipidemia: evidence of a protective allele depletion

    OpenAIRE

    Malloy Mary J; Pullinger Clive R; Kulkarni Medha V; Wung Shu-Fen; Kane John P; Aouizerat Bradley E

    2006-01-01

    Abstract Background Lipoprotein Lipase (LPL), a key enzyme in lipid metabolism, catalyzes the hydrolysis of triglycerides (TG) from TG-rich lipoproteins, and serves a bridging function that enhances the cellular uptake of lipoproteins. Abnormalities in LPL function are associated with pathophysiological conditions, including familial combined hyperlipidemia (FCH). Whereas two LPL susceptibility alleles were found to co-segregate in a few FCH kindred, a role for common, protective alleles rema...

  5. Regulation of Mutant p53 Protein Expression

    OpenAIRE

    Vijayakumaran, Reshma; Tan, Kah Hin; Miranda, Panimaya Jeffreena; Haupt, Sue; Haupt, Ygal

    2015-01-01

    For several decades, p53 has been detected in cancer biopsies by virtue of its high protein expression level which is considered indicative of mutation. Surprisingly, however, mouse genetic studies revealed that mutant p53 is inherently labile, similar to its wild type (wt) counterpart. Consistently, in response to stress conditions, both wt and mutant p53 accumulate in cells. While wt p53 returns to basal level following recovery from stress, mutant p53 remains stable. In part, this can be e...

  6. Cholesterol transfer from normal and atherogenic low density lipoproteins to Mycoplasma membranes

    International Nuclear Information System (INIS)

    The purpose of this study was to determine whether the free cholesterol of hypercholesterolemic low density lipoprotein from cholesterol-fed nonhuman primates has a greater potential for surface transfer to cell membranes than does the free cholesterol of normal low density lipoprotein. The low density lipoproteins were isolated from normal and hypercholesterolemic rhesus and cynomolgus monkeys, incubated with membranes from Acholeplasma laidlawii, a mycoplasma species devoid of cholesterol in its membranes, and the mass transfer of free cholesterol determined by measuring membrane cholesterol content. Since these membranes neither synthesize nor esterify cholesterol, nor degrade the protein or cholesterol ester moieties of low density lipoprotein, they are an ideal model with which to study differences in the cholesterol transfer potential of low density lipoprotein independent of the uptake of the intact low density lipoprotein particle. These studies indicate that, even though there are marked differences in the cholesterol composition of normal and hypercholesterolemic low density lipoproteins, this does not result in a greater chemical potential for surface transfer of free cholesterol. Consequently, if a difference in the surface transfer of free cholesterol is responsible for the enhanced ability of hypercholesterolemic low density lipoprotein to promote cellular cholesterol accumulation and, perhaps, also atherosclerosis, it must be the result of differences in the interaction to the hypercholesterolemic low density lipoprotein with the more complicated mammalian cell membranes, rather than differences in the chemical potential for cholesterol transfer

  7. Allele Specific p53 Mutant Reactivation

    OpenAIRE

    Yu, Xin; Vazquez, Alexei; Levine, Arnold J.; Carpizo, Darren R.

    2012-01-01

    Rescuing the function of mutant p53 protein is an attractive cancer therapeutic strategy. Using the NCI anticancer drug screen data, we identified two compounds from the thiosemicarbazone family that manifest increased growth inhibitory activity in mutant p53 cells, particularly for the p53R175 mutant. Mechanistic studies reveal that NSC319726 restores WT structure and function to the p53R175 mutant. This compound kills p53R172H knock-in mice with extensive apoptosis and inhibits xenograft tu...

  8. Biochemical and histological characterization of tomato mutants

    Directory of Open Access Journals (Sweden)

    Carolina C. Monteiro

    2012-06-01

    Full Text Available Biochemical responses inherent to antioxidant systems as well morphological and anatomical properties of photomorphogenic, hormonal and developmental tomato mutants were investigated. Compared to the non-mutant Micro-Tom (MT, we observed that the malondialdehyde (MDA content was enhanced in the diageotropica (dgt and lutescent (l mutants, whilst the highest levels of hydrogen peroxide (H2O2 were observed in high pigment 1 (hp1 and aurea (au mutants. The analyses of antioxidant enzymes revealed that all mutants exhibited reduced catalase (CAT activity when compared to MT. Guaiacol peroxidase (GPOX was enhanced in both sitiens (sit and notabilis (not mutants, whereas in not mutant there was an increase in ascorbate peroxidase (APX. Based on PAGE analysis, the activities of glutathione reductase (GR isoforms III, IV, V and VI were increased in l leaves, while the activity of superoxide dismutase (SOD isoform III was reduced in leaves of sit, epi, Never ripe (Nr and green flesh (gf mutants. Microscopic analyses revealed that hp1 and au showed an increase in leaf intercellular spaces, whereas sit exhibited a decrease. The au and hp1 mutants also exhibited a decreased in the number of leaf trichomes. The characterization of these mutants is essential for their future use in plant development and ecophysiology studies, such as abiotic and biotic stresses on the oxidative metabolism.Neste trabalho, analisamos as respostas bioquímicas inerentes ao sistema antioxidante, assim como propriedades morfológicas e anatômicas de mutantes fotomorfogenéticos e hormonais de tomateiro. Comparados ao não mutante Micro-Tom (MT, observamos que o conteúdo de malondialdeído (MDA aumentou nos mutantes diageotropica (dgt e lutescent (l, enquanto os maiores níveis de H2O2 foram encontrados nos mutantes high pigment 1 (hp1 e aurea (au. Análises de enzimas antioxidantes mostraram que todos os mutantes reduziram a atividade de catalase (CAT quando comparado a MT. A

  9. Recent advances in lipoprotein and atherosclerosis: A nutrigenomic approach

    Directory of Open Access Journals (Sweden)

    López, Sergio

    2009-03-01

    Full Text Available Atherosclerosis is a disease in which multiple factors contribute to the degeneration of the vascular wall. Many risk factors have been identified as having influence on the progression of atherosclerosis among them, the type of diet. Multifactorial interaction among lipoproteins, vascular wall cells, and inflammatory mediators has been recognised as the basis of atherogenesis. Dietary intake affects lipoprotein concentration and composition providing risk or protection at several stages of atherosclerosis. More intriguingly, it has been demonstrated that the extent to which each lipid or lipoprotein is associated with cardiovascular disease depends on the time to last meal; thus, postprandial lipoproteins, main lipoproteins in blood after a high-fat meal, have been shown to strongly influence atherogenesis. As a complex biological process, the full cellular and molecular characterization of atherosclerosis derived by diet, calls for application of the newly developing “omics” techniques of analysis. This review will considered recent studies using high-throughput technologies and a nutrigenomic approach to reveal the patho-physiological effects that the fasting and postprandial lipoproteins may exert on the vascular wall.La aterosclerosis es una enfermedad en la que múltiples factores, entre los que se encuentra la dieta, contribuyen a la degradación de la pared vascular. En la etiología de la aterogénesis son determinantes las lipoproteínas plasmáticas y los distintos tipos celulares de la pared vascular, incluyendo una respuesta inflamatoria. La ingesta de alimentos afecta la concentración y composición de las lipoproteínas, ejerciendo un papel de riesgo o protector durante las diferentes etapas del proceso aterosclerótico. Es importante destacar que la naturaleza de las lipoproteínas y por lo tanto su papel en la enfermedad cardiovascular, también depende del tiempo transcurrido entre comidas. Por ejemplo, las lipoprote

  10. Transport of phytanic acid on lipoproteins in Refsum disease.

    Science.gov (United States)

    Wierzbicki, A S; Sankaralingam, A; Lumb, P J; Hardman, T C; Sidey, M C; Gibberd, F B

    1999-02-01

    Patients with Refsum disease accumulate significant quantities of phytanic acid in adipose and neural tissue. The accumulation can be reversed by following a diet low in phytanic acid, yet the mechanism of transport of this fatty acid is obscure. We investigated the distribution of phytanic acid in different lipoprotein subfractions in 11 patients with Refsum disease and 9 unaffected siblings. Plasma phytanic acid was distributed on VLDL (16.2% +/- 12.2%), IDL (1.77% +/- 1.64%), LDL (34.8% +/- 12.6%) and HDL (14.3% +/- 7.87%). No correlations with any parameter were seen with total phytanic acid content. Weak nonsignificant correlations were found with the fractional distribution of phytanic acid and VLDL triglyceride (r = 0.35; p = 0.12) and plasma HDL-cholesterol (r = 0.32; p = 0.16) and with LDL:HDL cholesterol ratio (r = 0.33; p = 0.14). Significant correlation of the fractional distribution of phytanic acid on lipoprotein particles was noted with the ratio of apolipoprotein B: apolipoprotein A1-containing particles (r = 0.46; p = 0.03) and apolipoprotein B: apolipoprotein A1 in HDL2 (r = 0.53; p = 0.01). This suggests that the import-export balance for phytanic acid in plasma is related to forward and reverse cholesterol transport on lipoprotein particles, and only weakly to plasma cholesterol and triglycerides. These ratios of apolipoprotein particles may play a significant role in determining the rate of phytanic acid elimination in patients with Refsum disease.

  11. The influence of lipoprotein(a on fibrinolytic activity

    Directory of Open Access Journals (Sweden)

    Rahajuningsih D. Setiabudy

    2004-09-01

    Full Text Available Lipoprotein(a is a plasma lipoprotein whose structure and composition are similar with low density lipoprotein (LDL with an addition of apo(a that is bound to apo B100. The structure of apo(a is similar with plasminogen, a proenzym in fibrinolytic system. Due to this similarity, it is assumed that Lp(a can inhibit plasminogen activity and decreases fibrinolytic activity. The purpose of this study is to prove that addition of Lp(a to normal plasma can inhibit fibrinolytic activity. Four healthy people whose fibrinogen levels, plasminogen activities and euglobulin clot lysis time were within normal range were enrolled in this study. Fibrinolytic activity were assessed by euglobulin clot lysis time (ECLT. In the first experiment, the addition of Lp(a was done before centrifugation to obtain euglobulin precipitates, while in the second experiment, Lp(a was added to the euglobulin precipitates. As a control, ECLT was performed in the plasma with the addition of NaCl 0.9% in the same volume with Lp(a. The results of the study showed that in the first experiment, there was no clot formation. It is assumed that Lp(a can bind fibrinogen and both of them floated in the supernatant, so there was no fibrinogen in the euglobulin precipitate that can be clotted by thrombin. In the second experiment, the clot did not dissolve until the fourth day. In conclusion, the addition of Lp(a to normal plasma can inhibit the activity of fibrinolytic system. (Med J Indones 2004; 13: 135-9 Keywords: plasminogen, fibrinogen, apo(a, euglobulin clot lysis time (ECLT

  12. Correlation studies between serum concentrations of zinc and lipoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Saiki, Mitiko; Alves, Edson R.; Vasconcellos, M.B.A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: mitiko@ipen.br, e-mail: eralves@ipen.br, e-mail: mbvascon@ipen.br; Sumita, Nairo M. [Universidade de Sao Paulo (USP), SP (Brazil). Hospital das Clinicas.Central Lab. Division and Laboratories of Medical Investigation (LIM-03)], e-mail: dlc.bioquimica@hcnet.usp.br; Jaluul, Omar; Jacob-Filho, Wilson [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina], e-mail: jaluul@uol.com.br, wiljac@usp.br

    2009-07-01

    In this study, serum zinc and lipoprotein concentrations were determined in order to assess the health status of an elderly population residing in Sao Paulo city, SP, Brazil. This population consisted of elderly considered healthy and participating of a 'Successful Ageing' program of the Sao Paulo University Medical School. Fasting blood samples were collected from 87 elderly individuals (63 females and 24 males) aged 60-91 and mean age of 72 +- 7 years. Zn concentrations were determined by neutron activation analysis at the IPEN/CNEN/ SP and, the lipoprotein (HDL, LDL and total cholesterol) concentrations were determined using routine analysis methods of the Central Laboratory Division, Hospital das Clinicas, FMUSP. Results obtained for Zn indicated that all the individuals presented this element within the recommended value. For total cholesterol and HDL-cholesterol concentrations, 96 % of elderly presented levels within the desired range but for LDL cholesterol concentrations only about 70.0 % of individuals were in the desired range. Serum concentration of Zn were positively correlated to LDL-cholesterol levels (correlation coefficient r = 0.21, p < 0.06). Furthermore, the ratios of [HDL-cholesterol] / [LDL-cholesterol] were negatively correlated with Zn concentrations (r = - 0.234, p < 0.04). The positive correlation found between the serum concentrations of Zn and LDL-cholesterol indicates the possible effect of this element in serum lipoprotein profiles. Thus ,these findings suggest that more investigations should be conducted on Zn supplementation in elderly subjects with cardiovascular diseases. (author)

  13. Cell wall sorting of lipoproteins in Staphylococcus aureus.

    OpenAIRE

    Navarre, W W; Daefler, S; Schneewind, O

    1996-01-01

    Many surface proteins are thought to be anchored to the cell wall of gram-positive organisms via their C termini, while the N-terminal domains of these molecules are displayed on the bacterial surface. Cell wall anchoring of surface proteins in Staphylococcus aureus requires both an N-terminal leader peptide and a C-terminal cell wall sorting signal. By fusing the cell wall sorting of protein A to the C terminus of staphylococcal beta-lactamase, we demonstrate here that lipoproteins can also ...

  14. Lipoprotein(a): Cellular Effects and Molecular Mechanisms

    OpenAIRE

    Kirsten Riches; Porter, Karen E

    2012-01-01

    Lipoprotein(a) (Lp(a)) is an independent risk factor for the development of cardiovascular disease (CVD). Indeed, individuals with plasma concentrations >20 mg/dL carry a 2-fold increased risk of developing CVD, accounting for ~25% of the population. Circulating levels of Lp(a) are remarkably resistant to common lipid lowering therapies, and there are currently no robust treatments available for reduction of Lp(a) apart from plasma apheresis, which is costly and labour intensive. The Lp(a) mo...

  15. Surface-Associated Lipoproteins Link Enterococcus faecalis Virulence to Colitogenic Activity in IL-10-Deficient Mice Independent of Their Expression Levels.

    Directory of Open Access Journals (Sweden)

    Soeren Ocvirk

    2015-06-01

    Full Text Available The commensal Enterococcus faecalis is among the most common causes of nosocomial infections. Recent findings regarding increased abundance of enterococci in the intestinal microbiota of patients with inflammatory bowel diseases and induction of colitis in IL-10-deficient (IL-10-/- mice put a new perspective on the contribution of E. faecalis to chronic intestinal inflammation. Based on the expression of virulence-related genes in the inflammatory milieu of IL-10-/- mice using RNA-sequencing analysis, we characterized the colitogenic role of two bacterial structures that substantially impact on E. faecalis virulence by different mechanisms: the enterococcal polysaccharide antigen and cell surface-associated lipoproteins. Germ-free wild type and IL-10-/- mice were monoassociated with E. faecalis wild type OG1RF or the respective isogenic mutants for 16 weeks. Intestinal tissue and mesenteric lymph nodes (MLN were collected to characterize tissue pathology, loss of intestinal barrier function, bacterial adhesion to intestinal epithelium and immune cell activation. Bone marrow-derived dendritic cells (BMDC were stimulated with bacterial lysates and E. faecalis virulence was additionally investigated in three invertebrate models. Colitogenic activity of wild type E. faecalis (OG1RF score: 7.2±1.2 in monoassociated IL-10-/- mice was partially impaired in E. faecalis lacking enterococcal polysaccharide antigen (ΔepaB score: 4.7±2.3; p<0.05 and was almost completely abrogated in E. faecalis deficient for lipoproteins (Δlgt score: 2.3±2.3; p<0.0001. Consistently both E. faecalis mutants showed significantly impaired virulence in Galleria mellonella and Caenorhabditis elegans. Loss of E-cadherin in the epithelium was shown for all bacterial strains in inflamed IL-10-/- but not wild type mice. Inactivation of epaB in E. faecalis reduced microcolony and biofilm formation in vitro, altered bacterial adhesion to intestinal epithelium of germ

  16. Lipoprotein apheresis in the management of severe hypercholesterolemia and of elevation of lipoprotein(a): current perspectives and patient selection

    Science.gov (United States)

    Julius, Ulrich

    2016-01-01

    This review reports the current situation with respect to therapeutic options (lifestyle and drugs) reducing the concentrations of atherogenic low-density lipoprotein cholesterol (LDL-C) and lipoprotein(a) (Lp[a]). Three lipoprotein apheresis (LA) principles have been realized: precipitation, filtration, and adsorption. Available LA methods are herein described in detail – major components, pumps, extracorporeal volume, treated volume, and anticoagulation. General features of all LA methods as well as pleotropic effects are elaborated. Indications for LA therapy are quoted: homozygous familial hypercholesterolemia (HCH), severe HCH, and isolated elevation of Lp(a) and progress of atherosclerotic disease. A major focus is on the evidence of the effect of LA on cardiovascular outcome data, and the most important publications are cited in this context. The best studies have been performed in patients with elevated Lp(a) in whom cardiovascular events were reduced by more than 80%. Major adverse effects and contraindications are listed. The impact of an LA therapy on patient quality of life and the requirements they have to fulfill are also highlighted. Finally, the future role of LA in treating high-risk patients with high LDL-C and/or high Lp(a) is discussed. It is probable that the significance of LA for treating patients with elevated LDL-C will decrease (with the exception of homozygous familial HCH) due to the application of PCSK9 inhibitors. The antisense oligonucleotide against apolipoprotein(a) could replace LA in patients with high Lp(a), provided positive outcome data are generated. PMID:27785114

  17. Radiation-sensitive mutants of yeast

    International Nuclear Information System (INIS)

    Nomenclature for various radiosensitive mutants of Saccharomyces cerevisiae is briefly discussed. Tables are presented to show results of allelism tests of most of the radiosensitive mutants isolated by various investigators together with a standardized rad locus designation and map positions of a number of rad loci in yeast

  18. Overexpression of human low density lipoprotein receptors leads to accelerated catabolism of Lp(a) lipoprotein in transgenic mice.

    OpenAIRE

    Hofmann, S L; Eaton, D L; Brown, M. S.; McConathy, W J; Goldstein, J L; Hammer, R. E.

    1990-01-01

    Lp(a) lipoprotein purified from human plasma bound with high affinity to isolated bovine LDL receptors on nitrocellulose blots and in a solid-phase assay. Lp(a) also competed with 125I-LDL for binding to human LDL receptors in intact fibroblasts. Binding led to cellular uptake of Lp(a) with subsequent stimulation of cholesterol esterification. After intravenous injection, human Lp(a) was cleared slowly from the plasma of normal mice. The clearance was markedly accelerated in transgenic mice t...

  19. Lipoprotein (a) and cardiovascular risk factors in children and adolescents

    Science.gov (United States)

    Palmeira, Ástrid Camêlo; Leal, Adriana Amorim de F.; Ramos, Nathaly de Medeiros N.; de Alencar F., José; Simões, Mônica Oliveira da S.; Medeiros, Carla Campos M.

    2013-01-01

    OBJECTIVE: To review the relationship between lipoprotein (a) [Lp(a)] and other risk factors for cardiovascular disease (CVD) in children and adolescents. DATA SOURCES: This systematic review included studies from 2001 to 2011, a ten-year time period. Epidemiological studies with children and/or adolescents published in English, Portuguese or Spanish and fully available online were included. The searches were performed in Science Direct, PubMed/Medline, BVS (Biblioteca Virtual em Saúde) and Cochrane Library databases, using the following combination of key-words: "lipoprotein a" and "cardiovascular diseases" and "obesity". DATA SYNTHESIS: Overall, 672 studies were obtained but only seven were included. Some studies assessed the family history for CVD. In all of them, Lp(a) levels were increased in patients with family history for CVD. There was also a positive correlation between Lp(a) and LDL-cholesterol, total cholesterol, and apolipoprotein B levels, suggesting an association between Lp(a) levels and the lipid profile. CONCLUSIONS: The evidence that CVD may originate in childhood and adolescence leads to the need for investigating the risk factors during this period in order to propose earlier and possibly more effective interventions to reduce morbidity and mortality rates. PMID:24473960

  20. Direct solid phase radioimmunoassay for chicken lipoprotein lipase

    International Nuclear Information System (INIS)

    A direct, noncompetitive immunoassay for chicken lipoprotein lipase (LPL) was developed. Antibodies to LPL were purified by immunoadsorption chromatography of goat antisera on an LPL-Sepharose column. Purified anti-LPL immunoglobulins were coupled covalently to hydrophilic polyacrylamide beads by a carbodiimide reagent. An excess amount of these beads was incubated with the sample on the standard to be assayed. The amount of LPL immobilized by the heads was then detected by an excess amount of 125I-labeled anti-LPL immunoglobulin. A linear relationship was obtained between the radioactivity bound and the amount of highly purified LPL used as a standard. The range of the assay was from 0.1 to 1.1 ng PLP. The assay was specific for chicken LPL and showed no cross-reactivity with liver lipase. It does not distinguish heat-inactivated from catalytically active enzyme species. This assay should be useful in studies of lipoprotein lipase where both catalytic activity and enzyme mass need to be quantitated

  1. Triacylglycerol kinetics in endotoxic rats with suppressed lipoprotein lipase activity

    Energy Technology Data Exchange (ETDEWEB)

    Bagby, G.J.; Corll, C.B.; Martinez, R.R.

    1987-07-01

    Hypertriglyceridemia observed in animals after bacterial endotoxin administration and some forms of sepsis can result from increased hepatic triacylglycerol (TG) output or decreased TG clearance by extrahepatic tissues. To differentiate between these two possibilities, TG and free fatty acid (FFA) kinetics were determined in control and endotoxin-injected rats 18 h after treatment. Plasma TG and FFA kinetics were assessed by a constant intravenous infusion with (9,10-/sup 3/H)palmitate-labeled very low-density lipoprotein and (1-/sup 14/C)palmitate bound to albumin, respectively. In addition, lipoprotein lipase (LPL) activity was determined in heart, skeletal muscle, and adipose tissue as well as in postheparin plasma of functionally hepatectomized, adrenalectomized, and gonadectomized rats. Plasma FFA acid concentrations were slightly increased in endotoxin-treated rats but their turnover did not differ from control. Endotoxin-treated rats had a threefold increase in plasma TG concentrations and decreased heart, skeletal muscle, and post-heparin plasma LPL activity. Plasma TG turnover was decreased, indicating that hypertriglyceridemia was not due to an increased TG output by the liver. Instead, the endotoxin-induced increase in plasma TG concentration was consequence of the 80% reduction in TG metabolic clearance rate. Thus, suppression of LPL activity in endotoxic animals impairs TG clearance resulting in hypertriglyceridemia. Furthermore, endotoxin administration reduced the delivery of TG-FFA to extrahepatic tissues because hepatic synthesis and secretion of TG from plasma FFA was decreased and LPL activity was suppressed.

  2. Hypertriglyceridemia and unusual lipoprotein subclass distributions associated with late pregnancy

    Energy Technology Data Exchange (ETDEWEB)

    Forte, T.M.; Kretchmer, N.; Silliman, K. (Lawrence Berkeley Lab., CA (United States))

    1991-03-15

    In the human adult population elevated plasma triglyceride (TG) levels are associated with decreased high density lipoprotein-cholesterol (HDL-C) levels and decreased HDL and LDL particle sizes. Late pregnancy is a hypertriglyceridemic state where little is known about LDL and HDL subpopulation distribution. Plasma lipids, apolipoproteins (apo) and lipoprotein subpopulations were examined in 36 pregnant women at 36 wk pregnancy and 6 wk postpartum and correlated with HDL and LDL size. There was a significant decrease in LDL diameter at 36 wk pre, 25 {plus minus} 0.7 nm compared, with 6 wk post, 26.4 {plus minus} 0.8 nm. A total of 97% of the 36 wk pre subjects had small dense LDL which paralleled increases in apoB concentration. Unlike LDL HDL at 36 wks pre showed a significant increase in larger sized particles where HDL{sub 2b} predominated. There was a positive correlation between HDL{sub 2b} mass and apoAl and HDL-C concentrations. Late pregnancy is a metabolic state where the predominance of large, HDL{sub 2b} particles is discordant with the predominance of small LDL and elevated TG. This annual metabolic pattern may in part be due to hormonal changes occurring in late pregnancy.

  3. Low density lipoproteins as circulating fast temperature sensors.

    Directory of Open Access Journals (Sweden)

    Ruth Prassl

    Full Text Available BACKGROUND: The potential physiological significance of the nanophase transition of neutral lipids in the core of low density lipoprotein (LDL particles is dependent on whether the rate is fast enough to integrate small (+/-2 degrees C temperature changes in the blood circulation. METHODOLOGY/PRINCIPAL FINDINGS: Using sub-second, time-resolved small-angle X-ray scattering technology with synchrotron radiation, we have monitored the dynamics of structural changes within LDL, which were triggered by temperature-jumps and -drops, respectively. Our findings reveal that the melting transition is complete within less than 10 milliseconds. The freezing transition proceeds slowly with a half-time of approximately two seconds. Thus, the time period over which LDL particles reside in cooler regions of the body readily facilitates structural reorientation of the apolar core lipids. CONCLUSIONS/SIGNIFICANCE: Low density lipoproteins, the biological nanoparticles responsible for the transport of cholesterol in blood, are shown to act as intrinsic nano-thermometers, which can follow the periodic temperature changes during blood circulation. Our results demonstrate that the lipid core in LDL changes from a liquid crystalline to an oily state within fractions of seconds. This may, through the coupling to the protein structure of LDL, have important repercussions on current theories of the role of LDL in the pathogenesis of atherosclerosis.

  4. Transport of cholesterol autoxidation products in rabbit lipoproteins

    International Nuclear Information System (INIS)

    Radiolabeled pure [4-14C] cholesterol was kept at 600C under air to autoxidize for 5 weeks, after which approximately 12% cholesterol oxidation products were formed. The mixture, suspended in gelatin, was given to rabbits by gastric gavage. Rabbits were killed 4, 24 and 48 h after treatment. Cholesterol and its autoxidation products were separated by thin-layer chromatography into 5 fractions and radioactivities of each fraction were measured. Percentages of each fraction of cholesterol oxidation products and cholesterol in the original mixture before administration and in the rabbit sera after administration were similar, suggesting that the rates of absorption of cholesterol oxidation products are not significantly different from that of cholesterol. Lipoproteins were fractioned by ultracentrifugation into VLDL, LDL and HDL. Radioactivities of each fraction in lipoproteins separated by thin layer chromatography showed that fractions containing cholestane-3β, 5α, 6β-triol, 7α- and 7β-hydroxycholesterol and 7-ketocholesterol were more selectively transported in VLDL, whereas most of the 25-hydroxycholesterol was present in LDL. HDL contained only minute amounts of cholesterol oxidation products. 22 refs

  5. High-density lipoprotein functionality in coronary artery disease.

    Science.gov (United States)

    Kosmas, Constantine E; Christodoulidis, Georgios; Cheng, Jeh-wei; Vittorio, Timothy J; Lerakis, Stamatios

    2014-06-01

    The role of high-density lipoprotein (HDL) in cardiovascular atheroprotection is well established. Epidemiological data have clearly demonstrated an inverse relationship between HDL levels and the risk for coronary artery disease, which is independent of the low-density lipoprotein levels. However, more recent data provide evidence that high HDL levels are not always protective and that under certain conditions may even confer an increased risk. Thus, a new concept has arisen, which stresses the importance of HDL functionality, rather than HDL concentration per se, in the assessment of cardiovascular risk. HDL functionality is genetically defined but can also be modified by several environmental and lifestyle factors, such as diet, smoking or certain pharmacologic interventions. Furthermore, HDL is consisted of a heterogeneous group of particles with major differences in their structural, biological and functional properties. Recently, the cholesterol efflux capacity from macrophages was proven to be an excellent metric of HDL functionality, because it was shown to have a strong inverse relationship with the risk of angiographically documented coronary artery disease, independent of the HDL and apolipoprotein A-1 levels, although it may not actually predict the prospective risk for cardiovascular events. Thus, improving the quality of HDL may represent a better therapeutic target than simply raising the HDL level, and assessment of HDL function may prove informative in refining our understanding of HDL-mediated atheroprotection.

  6. Identification of a Novel Lipoprotein Regulator of Clostridium difficile Spore Germination.

    Directory of Open Access Journals (Sweden)

    Kelly A Fimlaid

    2015-10-01

    Full Text Available Clostridium difficile is a Gram-positive spore-forming pathogen and a leading cause of nosocomial diarrhea. C. difficile infections are transmitted when ingested spores germinate in the gastrointestinal tract and transform into vegetative cells. Germination begins when the germinant receptor CspC detects bile salts in the gut. CspC is a subtilisin-like serine pseudoprotease that activates the related CspB serine protease through an unknown mechanism. Activated CspB cleaves the pro-SleC zymogen, which allows the activated SleC cortex hydrolase to degrade the protective cortex layer. While these regulators are essential for C. difficile spores to outgrow and form toxin-secreting vegetative cells, the mechanisms controlling their function have only been partially characterized. In this study, we identify the lipoprotein GerS as a novel regulator of C. difficile spore germination using targeted mutagenesis. A gerS mutant has a severe germination defect and fails to degrade cortex even though it processes SleC at wildtype levels. Using complementation analyses, we demonstrate that GerS secretion, but not lipidation, is necessary for GerS to activate SleC. Importantly, loss of GerS attenuates the virulence of C. difficile in a hamster model of infection. Since GerS appears to be conserved exclusively in related Peptostreptococcaeace family members, our results contribute to a growing body of work indicating that C. difficile has evolved distinct mechanisms for controlling the exit from dormancy relative to B. subtilis and other spore-forming organisms.

  7. CMPD: cancer mutant proteome database.

    Science.gov (United States)

    Huang, Po-Jung; Lee, Chi-Ching; Tan, Bertrand Chin-Ming; Yeh, Yuan-Ming; Julie Chu, Lichieh; Chen, Ting-Wen; Chang, Kai-Ping; Lee, Cheng-Yang; Gan, Ruei-Chi; Liu, Hsuan; Tang, Petrus

    2015-01-01

    Whole-exome sequencing, which centres on the protein coding regions of disease/cancer associated genes, represents the most cost-effective method to-date for deciphering the association between genetic alterations and diseases. Large-scale whole exome/genome sequencing projects have been launched by various institutions, such as NCI, Broad Institute and TCGA, to provide a comprehensive catalogue of coding variants in diverse tissue samples and cell lines. Further functional and clinical interrogation of these sequence variations must rely on extensive cross-platforms integration of sequencing information and a proteome database that explicitly and comprehensively archives the corresponding mutated peptide sequences. While such data resource is a critical for the mass spectrometry-based proteomic analysis of exomic variants, no database is currently available for the collection of mutant protein sequences that correspond to recent large-scale genomic data. To address this issue and serve as bridge to integrate genomic and proteomics datasets, CMPD (http://cgbc.cgu.edu.tw/cmpd) collected over 2 millions genetic alterations, which not only facilitates the confirmation and examination of potential cancer biomarkers but also provides an invaluable resource for translational medicine research and opportunities to identify mutated proteins encoded by mutated genes.

  8. Study on culturing Trichodema mutants

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-ai; WANG Wei-ming

    2004-01-01

    @@ Trichodema mutants strains T5, T0803, T1010, T1003were cultured in different conditions and media, also in the presence of fungicides at 40 mg/kg (CK or procymidone + chlorothalonil, or maneb or phosethyl-Al) . The pH values of media were 5, 6, 7 and 8 and hyphae were grown at temperatures of 15, 20, 25 and 30 ℃. After being cultured for 3, 4, 5, or 6 days, the strains were transferred at a lower temperature to sporulate (20℃) Obtained data were analyzed statistically, with the orthogonal array and ranges (R) differing dependes on the treatments (R = 40.0,42.4, 48.0, 62.8,107.0). The results indicated that the most important factor was the nature of the strain (R =107.0), while the change in temperature and time of cultivation produced the lowest effect (R =40.0). Each factor variance was significant and A3B4C2D1E3 was the optimum combined condition, in which strain T1010 grew more quickly and sporulated most.

  9. Effects of Anabolic Steroids on Lipoprotein Profiles of Female Weight Lifters.

    Science.gov (United States)

    Moffatt, Robert J.; And Others

    1990-01-01

    This study examined the effects of resistance exercise and anabolic steroids on lipoprotein profiles of female weightlifters. The study found that women who participate in resistance training have better lipoprotein profiles than their sedentary counterparts, but these changes do not offset the deleterious effects of steroid use. (SM)

  10. Adaptive immune response to lipoproteins of Staphylococcus aureus in healthy subjects

    NARCIS (Netherlands)

    Vu, Chi Hai; Kolata, Julia; Stentzel, Sebastian; Beyer, Anica; Salazar, Manuela Gesell; Steil, Leif; Pané-Farré, Jan; Rühmling, Vanessa; Engelmann, Susanne; Götz, Friedrich; van Dijl, Jan Maarten; Hecker, Michael; Mäder, Ulrike; Schmidt, Frank; Völker, Uwe; Bröker, Barbara M

    2016-01-01

    Staphylococcus aureus is a frequent commensal but also a dangerous pathogen, causing many forms of infection ranging from mild to life-threatening conditions. Among its virulence factors are lipoproteins, which are anchored in the bacterial cell membrane. Lipoproteins perform various functions in co

  11. Lipoprotein(a) concentration and the risk of coronary heart disease, stroke, and nonvascular mortality

    DEFF Research Database (Denmark)

    (Tybjaerg-Hansen, A.) The Fibrinogen Studies Collaboration.The Copenhagen City Heart Study; Tybjærg-Hansen, Anne

    2009-01-01

    CONTEXT: Circulating concentration of lipoprotein(a) (Lp[a]), a large glycoprotein attached to a low-density lipoprotein-like particle, may be associated with risk of coronary heart disease (CHD) and stroke. OBJECTIVE: To assess the relationship of Lp(a) concentration with risk of major vascular ...

  12. Should we change our lipid management strategies to focus on non-high-density lipoprotein cholesterol?

    NARCIS (Netherlands)

    J.S. Rana; S.M. Boekholdt

    2010-01-01

    Purpose of review Despite aggressive low-density lipoprotein cholesterol lowering, patients continue to be at significant risk of cardiovascular events. Assessment of non-high-density lipoprotein cholesterol (non-HDL-C) provides a measure of cholesterol contained in all atherogenic particles. In the

  13. Genetic evidence that lipoprotein(a) associates with atherosclerotic stenosis rather than venous thrombosis

    DEFF Research Database (Denmark)

    Kamstrup, Pia R; Tybjærg-Hansen, Anne; Nordestgaard, Børge G

    2012-01-01

    The aim of the present study was to determine whether lipoprotein(a) [Lp(a)], considered a causal risk factor for cardiovascular disease, primarily promotes thrombosis or atherosclerosis.......The aim of the present study was to determine whether lipoprotein(a) [Lp(a)], considered a causal risk factor for cardiovascular disease, primarily promotes thrombosis or atherosclerosis....

  14. 21 CFR 866.5580 - Alpha-1-lipoprotein immuno-logical test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alpha-1-lipoprotein immuno-logical test system. 866.5580 Section 866.5580 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN....5580 Alpha-1-lipoprotein immuno-logical test system. (a) Identification. An...

  15. In vivo transfer of lipoprotein(a) into human atherosclerotic carotid arterial intima

    DEFF Research Database (Denmark)

    Nielsen, Lars Bo; Grønholdt, Marie-Louise; Schroeder, T V;

    1997-01-01

    The aim of this study was to compare the atherogenic potential of lipoprotein(a) [Lp(a)] and LDL by measuring the intimal clearance of these two plasma lipoproteins in the atherosclerotic intima of the human carotid artery in vivo. Autologous 131I-Lp(a) and 125I-LDL were mixed and reinjected intr...

  16. Changes in lipids and lipoprotein particle concentrations after interruption of antiretroviral therapy

    DEFF Research Database (Denmark)

    Lampe, Fiona C; Duprez, Daniel A; Kuller, Lewis H;

    2010-01-01

    The effect of interruption of antiretroviral therapy (ART) on lipoprotein particle subclasses has not been studied. We examined short-term changes in lipids and lipoprotein particles among 332 HIV-infected individuals randomized to interrupt or continue ART in the "Strategies for Management of An...

  17. PLASMA-LIPOPROTEIN ABNORMALITIES IN TYPE-1 (INSULIN-DEPENDENT) DIABETES-MELLITUS

    NARCIS (Netherlands)

    DULLAART, RPF

    1995-01-01

    Lipoprotein abnormalities may well contribute to the increased risk of coronary heart disease, cerebrovascular disease and peripheral vascular disease observed in type 1 (insulin-dependent) diabetes mellitus. The spectrum of diabetes-associated changes in lipoprotein metabolism is discussed. The pla

  18. Effect of Dietary Fatty Acids on Human Lipoprotein Metabolism: A Comprehensive Update

    Directory of Open Access Journals (Sweden)

    Esther M.M. Ooi

    2015-06-01

    Full Text Available Dyslipidemia is a major risk factor for cardiovascular disease (CVD. Dietary fatty-acid composition regulates lipids and lipoprotein metabolism and may confer CVD benefit. This review updates understanding of the effect of dietary fatty-acids on human lipoprotein metabolism. In elderly participants with hyperlipidemia, high n-3 polyunsaturated fatty-acids (PUFA consumption diminished hepatic triglyceride-rich lipoprotein (TRL secretion and enhanced TRL to low-density lipoprotein (LDL conversion. n-3 PUFA also decreased TRL-apoB-48 concentration by decreasing TRL-apoB-48 secretion. High n-6 PUFA intake decreased very low-density lipoprotein (VLDL cholesterol and triglyceride concentrations by up-regulating VLDL lipolysis and uptake. In a study of healthy subjects, the intake of saturated fatty-acids with increased palmitic acid at the sn-2 position was associated with decreased postprandial lipemia. Low medium-chain triglyceride may not appreciably alter TRL metabolism. Replacing carbohydrate with monounsaturated fatty-acids increased TRL catabolism. Trans-fatty-acid decreased LDL and enhanced high-density lipoprotein catabolism. Interactions between APOE genotype and n-3 PUFA in regulating lipid responses were also described. The major advances in understanding the effect of dietary fatty-acids on lipoprotein metabolism has centered on n-3 PUFA. This knowledge emphasizes the importance of regulating lipoprotein metabolism as a mode to improve plasma lipids and potentially CVD risk. Additional studies are required to better characterize the cardiometabolic effects of other dietary fatty-acids.

  19. Gene therapy for genetic lipoprotein lipase deficiency : from promise to practice

    NARCIS (Netherlands)

    Nierman, M C; Rip, J; Twisk, J; Meulenberg, J J M; Kastelein, J J P; Stroes, E S G; Kuivenhoven, J A

    2005-01-01

    Lipoprotein lipase (LPL) deficiency is a rare, hereditary disorder of lipoprotein metabolism characterised by severely increased triglyceride levels, and associated with an increased risk for pancreatitis. Since no adequate treatment modality is available for this disorder, we set out to develop an

  20. Hormone-induced rearrangement of locust haemolymph lipoproteins The involvement of glycoprotein C2

    NARCIS (Netherlands)

    Horst, D.J. van der; Doorn, J.M. van; Beenakkers, A.M.Th.

    1984-01-01

    Formation of lipoprotein A⁺ and elevation of lipoprotein fraction O in locust (Locusta migratoria migratorioides) haemolymph as induced by adipokinetic hormone (AKH) includes the participation of non-lipid carrying proteins (fraction C), which was examined in more detail. By using gel filtration chr

  1. Effect of omega-3 fatty acids on the oxylipin composition of lipoproteins in hypertriglyceridemic, statin-treated subjects

    Science.gov (United States)

    Background: Oxylipins mediate many physiological processes, including inflammation and vascular function. Generally considered local and transient, we suggest their presence in lipoproteins indicates they also mediate the effects lipoproteins have on inflammation and vascular biology. To support th...

  2. Total and High-Density Lipoprotein Cholesterol in Adults: National Health and Nutrition Examination Survey, 2011-2012

    Science.gov (United States)

    ... National Technical Information Service NCHS Total and High-density Lipoprotein Cholesterol in Adults: National Health and Nutrition ... less than 10% of women) had low high-density lipoprotein (HDL) cholesterol during 2011–2012. The percentage ...

  3. Effect of a new herbo-mineral hypolipidemic agent on plasma lipoprotein pattern in rat atherosclerosis.

    Science.gov (United States)

    Tarvady, S; Dhar, S C

    1990-07-01

    Hyperlipidemia was induced in rats by feeding an atherogenic diet for 5 months. The effect of administration of an indigenous hypolipidemic agent, Anna Kaara Raaja Sindhooram (AKRS) on the plasma lipoprotein profile was studied in the presence and absence of dietary lipid stimuli. Hyperlipidemia produced an enormous increase in the cholesterol and triglyceride contents of the low density (LDL) and very low density (VLDL) lipoprotein fractions and reduced the level of the putative non-atherogenic high density cholesterol (HDL-C). The agarose gel electrophoretic pattern showed a decrease in alpha-lipoproteins and an increase in beta-lipoproteins in the hyperlipidemic rats. AKRS treatment for 5 months altered the lipoprotein pattern favourably by raising HDL-C and lowering LDL-C in the treated rats. PMID:2272653

  4. Lipoprotein(a) and ischemic heart disease-A causal association? A review

    DEFF Research Database (Denmark)

    Kamstrup, P.R.

    2010-01-01

    randomized clinical trials, genetic studies, such as Mendelian randomization studies, can also support claims of causality. Levels of lipoprotein(a) are primarily determined by variation in the LPA gene coding for the apolipoprotein(a) moiety of lipoprotein(a), and genetic epidemiologic studies have......The aim of this review is to summarize present evidence of a causal association of lipoprotein(a) with risk of ischemic heart disease (IHD). Evidence for causality includes reproducible associations of a proposed risk factor with risk of disease in epidemiological studies, evidence from in vitro...... documented association of LPA copy number variants, influencing levels of lipoprotein(a), with risk of IHD. In conclusion, results from epidemiologic, in vitro, animal, and genetic epidemiologic studies support a causal association of lipoprotein(a) with risk of IHD, while results from randomized clinical...

  5. Hepatic Lipase: a Comprehensive View of its Role on Plasma Lipid and Lipoprotein Metabolism.

    Science.gov (United States)

    Kobayashi, Junji; Miyashita, Kazuya; Nakajima, Katsuyuki; Mabuchi, Hiroshi

    2015-01-01

    Hepatic lipase (HL) is a key enzyme catalyzing the hydrolysis of triglycerides (TG) and phospholipids (PLs) in several lipoproteins. It is generally recognized that HL is involved in the remodeling of remnant, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and the production of small, dense low-density lipoproteins (sd-LDLs).On the other hand, it is unclear whether HL accelerates or retards atherosclerosis. From the clinical point of view, HL deficiency may provide useful information on answering this question, but the rarity of this disease makes it impossible to conduct epidemiological study.In this review, we describe a comprehensive and updated view of the clinical significance of HL on lipid and lipoprotein metabolism. PMID:26194979

  6. Characterization of Lipoprotein Lipases interactions with Sortilin and SorLA

    DEFF Research Database (Denmark)

    Klinger, Stine Christensen

    . The present study describes their trafficking of two ligands, lipoprotein lipase and apolipoprotein A-V, which are integral parts of the lipid metabolism. Lipoprotein lipase is found at the luminal side of capillary endothelial cells, where it is involved in the conversion of circulating triglycerides to free...... fatty acids, which in turn are used as an energy source in muscle cells or as an energy reserve in adipose tissue. Lack of lipoprotein lipase leads to an elevated level of plasma lipids and results in increased risk of cardiovascular diseases. The regulation of lipoprotein lipase expression takes place...... at both transcriptional and posttranslational levels. While the transcriptional regulation of the lipase is well described, the posttranslational mechanisms affecting lipoprotein lipase expression are far from understood. The functions of the recently discovered apolipoprotein A-V are still a subject...

  7. Characterization of hepatic low density lipoprotein binding and cholesterol metabolism in normal and homozygous familial hypercholesterolemic subjects.

    OpenAIRE

    Hoeg, J M; Demosky, S J; Schaefer, E.J.; Starzl, T.E.; Brewer, H B

    1984-01-01

    Patients with familial hypercholesterolemia have elevated levels of plasma low density lipoproteins (LDL), increased hepatic synthesis of apolipoprotein B-containing lipoproteins, defective binding of low density lipoproteins to fibroblasts, and premature atherosclerosis. The role of a hepatic low density lipoprotein receptor in normal man and its importance in the pathogenesis of familial hypercholesterolemia have not been previously determined. In the present study, direct comparison was ma...

  8. Effect of Omega-3 Fatty Acid Ethyl Esters on the Oxylipin Composition of Lipoproteins in Hypertriglyceridemic, Statin-Treated Subjects

    OpenAIRE

    NEWMAN, JOHN W.; Pedersen, Theresa L.; Brandenburg, Verdayne R.; Harris, William S.; Shearer, Gregory C.

    2014-01-01

    Background Oxylipins mediate inflammation, vascular tension, and more. Their presence in lipoproteins could explain why lipoproteins mediate nearly identical activities. Methods To determine how oxylipins are distributed in the lipoproteins of hypertriglyceridemic subjects, and whether omega-3 fatty acids alter them in a manner consistent with improved cardiovascular health, we recruited 15 dyslipidemic subjects whose levels of low density lipoprotein cholesterol (LDL-C) were at goal but who ...

  9. Crystal structure of the Campylobacter jejuni Cj0090 protein reveals a novel variant of the immunoglobulin fold among bacterial lipoproteins

    OpenAIRE

    Paek, Seonghee; Kawai, Fumihiro; Choi, Kyoung-Jae; Yeo, Hye-Jeong

    2012-01-01

    Bacterial lipoproteins play an important role in bacterial pathogenesis and physiology. The genome of Campylobacter jejuni, a major foodborn pathogen, is predicted to contain over 20 lipoproteins. However, the functions of the majority of C. jejuni lipoproteins remain unknown. The Cj0090 protein is encoded by a lipoprotein operon composed of cj0089, cj0090, and cj0091. Here, we report the crystal structure of Cj0090 at 1.9 Å resolution, revealing a novel variant of the immunoglobulin fold wit...

  10. Temperature-sensitive rubisco mutant of Chlamydomonas

    International Nuclear Information System (INIS)

    The Chlamydomonas reinhardtii mutant 68-4PP is a temperature-sensitive mutant that lacks photosynthetic ability at 350C, but is able to grow photosynthetically at 250C. Genetic analysis indicated that 68-4PP is a chloroplast mutant that is allelic with known Rubisco large-subunit structural-gene mutants, implying that 68-4PP also resulted from a mutation in the large-subunit gene. The 68-4PP mutant has about 35% of the wild-type level of Rubisco holoenzyme and carboxylase activity when grown at 250C, but it has less than 10% of normal holoenzyme and carboxylase activity when grown at 350C. However, [35S]-sulfate pulse labeling showed that Rubisco subunits were synthesized at normal rates at both temperatures. More significantly, the ratio of carboxylase activity in the absence and presence of oxygen at a limiting CO2 concentration (6.6 μM) was about 2.2 for the mutant enzyme, as compared to about 3.0 for the wild-type enzyme. The decreased ratio of the mutant enzyme is maternally inherited, indicating that this reduced oxygen sensitivity results from a mutation in chloroplast DNA. The authors have recently cloned the 68-4PP Rubisco large-subunit gene, and DNA sequencing is in progress

  11. Induction of Mutants in Durum Wheat

    International Nuclear Information System (INIS)

    This investigation presents a breeding program for induction and development of a new genotype of durum wheat, resistant to lodging with high yield, by irradiation durum wheat hybrids (F2) with gamma rays 100 Gy, during 1990-1997 cultivation seasons. This program involves: induction of variability, selection evaluation of the mutants at three locations: Twaitha (Baghdad) Latifya ( Babylon) and Swari (Kutt). All mutants showed resistance to lodging and there was a significant reduction in plant height. Mutant SIXIZ-22 surpassed other mutants and its origin in lodging resistance and plant height (83.5,82.8 and 89.4 cm) in the three locations at generation M5 and M6, respectively. Also, there were significant differences between mutant and their origin in the number of spikes/M2 and grain yild during the two successive generation. On the other hand, mutant IZxCO-105 surpassed other mutants in the number of spikes/M2 (231.8,242.3 and 292) and grain yield (4336,3376 and 5232 kg/ha) in all testing location, respectively . (authors) 14 refs., 4 tabs

  12. Characterization and Purification of Polydisperse Reconstituted Lipoproteins and Nanolipoprotein Particles

    Directory of Open Access Journals (Sweden)

    Paul D. Hoeprich

    2009-07-01

    Full Text Available Heterogeneity is a fact that plagues the characterization and application of many self-assembled biological constructs. The importance of obtaining particle homogeneity in biological assemblies is a critical goal, as bulk analysis tools often require identical species for reliable interpretation of the results—indeed, important tools of analysis such as x-ray diffraction typically require over 90% purity for effectiveness. This issue bears particular importance in the case of lipoproteins. Lipid-binding proteins known as apolipoproteins can self assemble with liposomes to form reconstituted high density lipoproteins (rHDLs or nanolipoprotein particles (NLPs when used for biotechnology applications such as the solubilization of membrane proteins. Typically, the apolipoprotein and phospholipids reactants are self assembled and even with careful assembly protocols the product often contains heterogeneous particles. In fact, size polydispersity in rHDLs and NLPs published in the literature are frequently observed, which may confound the accurate use of analytical methods. In this article, we demonstrate a procedure for producing a pure, monodisperse NLP subpopulation from a polydisperse self-assembly using size exclusion chromatography (SEC coupled with high resolution particle imaging by atomic force microscopy (AFM. In addition, NLPs have been shown to self assemble both in the presence and absence of detergents such as cholate, yet the effects of cholate on NLP polydispersity and separation has not been systematically examined. Therefore, we examined the separation properties of NLPs assembled in both the absence and presence of cholate using SEC and native gel electrophoresis. From this analysis, NLPs prepared with and without cholate showed particles with well defined diameters spanning a similar size range. However, cholate was shown to have a dramatic affect on NLP separation by SEC and native gel electrophoresis. Furthermore, under

  13. Facile Synthesis and Adsorption Properties of Phosphonated Cellulose Beads for Selective Removal of Low-density Lipoprotein

    Institute of Scientific and Technical Information of China (English)

    Hao Feng YU; Guo Qi FU; Li LIU; Bing Lin HE

    2006-01-01

    A novel low-density lipoprotein adsorbent was prepared simply by directly phosphonating porous cellulose beads. Tests in vitro demonstrated that this adsorbent showed quite good adsorption performance for selective removal of low-density lipoprotein from human plasma. The effects of preparation conditions on the lipoprotein sorption properties of the resulted adsorbent were investigated. The adsorption dynamics was also examined.

  14. Pathophysiological concentrations of glucose promote oxidative modification of low density lipoprotein by a superoxide-dependent pathway.

    OpenAIRE

    Kawamura, M.; Heinecke, J W; Chait, A.

    1994-01-01

    Oxidized lipoproteins may be important in the pathogenesis of atherosclerosis. Because diabetic subjects are particularly prone to vascular disease, and glucose autoxidation and protein glycation generate reactive oxygen species, we explored the role of glucose in lipoprotein oxidation. Glucose enhanced low density lipoprotein (LDL) oxidation at concentrations seen in the diabetic state. Conjugated dienes, thiobarbituric acid reactive substances, electrophoretic mobility, and degradation by m...

  15. Productive potentials of short stemmed wheat mutants

    International Nuclear Information System (INIS)

    Air dry F2 seeds of the cross Skorospelka-35xMexipak were gamma irradiated (5 krad). It was established that the new short-stemmed wheat mutants can olay an important role both in hybrid combination breeding and as direct cultivars. Some of these mutants (No. 65, 67-I, 67-II, etc.), proved very promising because of their high productivity combined with other valuable biological and economic characters. The results obtained show also the great potentials and the perspectives of the method of combining hybrid and induced mutant variability. (author)

  16. Bio F1B hamster: a unique animal model with reduced lipoprotein lipase activity to investigate nutrient mediated regulation of lipoprotein metabolism

    Directory of Open Access Journals (Sweden)

    Cornish Marion L

    2007-12-01

    Full Text Available Abstract Background Bio F1B hamster is an inbred hybrid strain that is highly susceptible to diet-induced atherosclerosis. We previously reported that feeding a high fat fish oil diet to Bio F1B hamster caused severe hyperlipidaemia. In this study we compared the effects of various diets in the Bio F1B hamster and the Golden Syrian hamster, which is an outbred hamster strain to investigate whether genetic background plays an important role in dietary fat mediated regulation of lipoprotein metabolism. We further investigated the mechanisms behind diet-induced hyperlipidaemia in F1B hamster. Methods The Bio F1B and Golden Syrian hamsters, 8 weeks old, were fed high fat diets rich in either monounsaturated fatty acids, an n-6: n-3 ratio of 5 or a fish oil diet for 4 weeks. Animals were fasted overnight and blood and tissue samples were collected. Plasma was fractionated into various lipoprotein fractions and assayed for triacylglycerol and cholesterol concentrations. Plasma lipoprotein lipase activity was measured using radioisotope method. Microsomal triglyceride transfer protein activity was measured in the liver and intestine. Plasma apolipoproteinB48, -B100 and apolipoprotein E was measured using Western blots. Two-way ANOVA was used to determine the effect of diet type and animal strain. Results The fish oil fed F1B hamsters showed milky plasma after a 14-hour fast. Fish oil feeding caused accumulation of apolipoproteinB48 containing lipoprotein particles suggesting hindrance of triglyceride-rich lipoprotein clearance. There was no significant effect of diet or strain on hepatic or intestinal microsomal triglyceride transfer protein activity indicating that hyperlipidaemia is not due to an increase in the assembly or secretion of lipoprotein particles. F1B hamsters showed significantly reduced levels of lipoprotein lipase activity, which was inhibited by fish oil feeding. Conclusion Evidence is presented for the first time that alterations in

  17. Effect of improving glycemic control in patients with type 2 diabetes mellitus on low-density lipoprotein size, electronegative low-density lipoprotein and lipoprotein-associated phospholipase A2 distribution.

    Science.gov (United States)

    Sánchez-Quesada, José L; Vinagre, Irene; de Juan-Franco, Elena; Sánchez-Hernández, Juan; Blanco-Vaca, Francisco; Ordóñez-Llanos, Jordi; Pérez, Antonio

    2012-07-01

    The aim of this study was to determine the effect of intensified hypoglycemic therapy in patients with type 2 diabetes mellitus on the distribution of lipoprotein-associated phospholipase A2 (Lp-PLA2) activity between high-density lipoprotein and low-density lipoprotein (LDL) and its relation with the lipid profile and other qualitative properties of LDL. Forty-two patients with type 2 diabetes on the basis of poor glycemic control and normal or near normal LDL cholesterol were recruited. Lifestyle counseling and pharmacologic hypoglycemic therapy were intensified to improve glycemic control, but lipid-lowering therapy was unchanged. At 4 ± 2 months, glycosylated hemoglobin had decreased by a mean of 2.1%, but the only effect on the lipid profile were statistically significant decreases in nonesterified fatty acids and apolipoprotein B concentration. LDL size increased and the proportion of electronegative LDL decreased significantly. In parallel, total Lp-PLA2 activity decreased significantly, promoting a redistribution of Lp-PLA2 activity toward a higher proportion in high-density lipoprotein. Improvements in glycemic control led to more marked changes in Lp-PLA2 activity and distribution in patients with diabetes who had not received previous lipid-lowering therapy. In conclusion, optimizing glycemic control in patients with type 2 diabetes promotes atheroprotective changes, including larger LDL size, decreased electronegative LDL, and a higher proportion of Lp-PLA2 activity in high-density lipoprotein. PMID:22481012

  18. Low density lipoprotein receptors: preliminary results on 'in vivo' study

    International Nuclear Information System (INIS)

    Plasmatic levels of low density lipoproteins (LDL) are regulated by the receptor pathway and most LDL receptor are located in the liver. A receptor defect due to genetic mutations of the LDL receptor gene is the cause of familial hypercholesterolemia (F.H.), a disease characterized by high cholesterol levels and premature atherosclerosis. Injections of autologous radiolabelled LDL, followed by hepatic scintiscanning, can be used to obtain 'in vivo' quantification of hepatic receptor activity, both in normal and hypercholesterolemic patients. In this study we observe no hepatic increase of radioactivity in patients affected by F.H., confirming the liver receptor defect. Scintigraphy is a non-invasive technique which can be used to diagnose this disease and to monitor the efficiacy of hypolipidemic therapy. (Authors)

  19. Transvascular lipoprotein transport in patients with chronic renal disease

    DEFF Research Database (Denmark)

    Jensen, Trine Krogsgaard; Nordestgaard, Børge Grønne; Feldt-Rasmussen, Bo;

    2004-01-01

    , determines the degree of atherosclerosis among patients with chronic renal disease. METHODS: We used an in vivo method for measurement of transvascular transport of low-density lipoprotein (LDL) in 21 patients with chronic renal disease and in 42 healthy control patients. Autologous 131-iodinated LDL...... was reinjected intravenously, and the 1-hour fractional escape rate was taken as index of transvascular transport. RESULTS: Transvascular LDL transport tended to be lower in patients with chronic renal disease than in healthy control patients [3.3 (95% CI 2.4-4.2) vs. 4.2 (3.7-4.2)%/hour; NS]. However...... with chronic renal disease, and healthy control patients [5.0 (3.2-7.8) vs. 3.0 (2.2-3.8) vs. 4.2 (3.6-4.8) %/hour; P

  20. Biominetic High Density Lipoproteins for the Delivery of Therapeutic Oligonucleotides

    Science.gov (United States)

    Tripathy, Sushant

    Advances in nanotechnology have brought about novel inorganic and hybrid nanoparticles with unique physico-chemical properties that make them suitable for a broad range of applications---from nano-circuitry to drug delivery. A significant part of those advancements have led to ground-breaking discoveries that have changed the approaches to formulation of therapeutics against diseases, such as cancer. Now-a-days the focus does not lie solely on finding a candidate small-molecule therapeutic with minimal adverse effects, but researchers are looking up to nanoparticles to improve biodistribution and biocompatibility profile of clinically proven therapeutics. The plethora of conjugation chemistries offered by currently extant inorganic nanoparticles have, in recent years, led to great leaps in the field of biomimicry---a modality that promises high biocompatibility. Further, in the pursuit of highly specific therapeutic molecules, researchers have turned to silencing oligonucleotides and some have already brought together the strengths of nanoparticles and silencing oligonucleotides in search of an efficacious therapy for cancer with minimal adverse effects. This dissertation work focuses on such a biomimetic platform---a gold nanoparticle based high density lipoprotein biomimetic (HDL NP), for the delivery of therapeutic oligonucleotides. The first chapter of this body of work introduces the molecular target of the silencing oligonucleotides---VEGFR2, and its role in the progression of solid tumor cancers. The background information also covers important aspects of natural high density lipoproteins (HDL), especially their innate capacity to bind and deliver exogenous and endogenous silencing oligonucleotides to tissues that express their high affinity receptor SRB1. We subsequently describe the synthesis of the biomimetic HDL NP and its oligonucleotide conjugates, and establish their biocompatibility. Further on, experimental data demonstrate the efficacy of silencing

  1. Brucella ovis PA mutants for outer membrane proteins Omp10, Omp19, SP41, and BepC are not altered in their virulence and outer membrane properties.

    Science.gov (United States)

    Sidhu-Muñoz, Rebeca S; Sancho, Pilar; Vizcaíno, Nieves

    2016-04-15

    Mutants in several genes have been obtained on the genetic background of virulent rough (lacking O-polysaccharide) Brucella ovis PA. The target genes encode outer membrane proteins previously associated with the virulence of smooth (bearing O-polysaccharide chains in the lipopolysaccharide) Brucella strains. Multiple attempts to delete omp16, coding for a homologue to peptidoglycan-associated lipoproteins, were unsuccessful, which suggests that Omp16 is probably essential for in vitro survival of B. ovis PA. Single deletion of omp10 or omp19-that encode two other outer membrane lipoproteins--was achieved, but the simultaneous removal of both genes failed, suggesting an essential complementary function between both proteins. Two other deletion mutants, defective in the Tol-C-homologue BepC or in the SP41 adhesin, were also obtained. Surprisingly when compared to previous results obtained with smooth Brucella, none of the B. ovis mutants showed attenuation in the virulence, either in the mouse model or in cellular models of professional and non-professional phagocytes. Additionally, and in contrast to the observations reported with smooth Brucella strains, several properties related to the outer membrane remained almost unaltered. These results evidence new distinctive traits between naturally rough B. ovis and smooth brucellae.

  2. Induced mutants for rice functional genomics

    International Nuclear Information System (INIS)

    Induced mutations have been playing important roles in both crop germplasm enhancement and new variety development. With the completion of the rice genome sequence, the study on functional genomics in rice has become a major task. Construction of rice mutant library is an essential approach for rice functional genomics study. This paper briefly reviewed several common techniques for generation of rice mutant library and its application in rice functional research, taking examples of developing rice chloroplast development related mutant library to provide the basic materials for functional genes cloning. A rice Chlorophyll (Chl) deficient mutant, yellow-green leaf1 (ygl1), was isolated, which showed yellow-green leaves in young plants with decreased Chl synthesis, increased level of tetrapyrrole intermediates, and delayed chloroplast development. Genetic analysis demonstrated that the phenotype of ygl1 was caused by a recessive mutation in a nuclear gene. The ygl1 locus was mapped to chromosome 5. A missense mutation was found in a highly conserved residue of YGL1 in the ygl1 mutant, resulting in reduction of the enzymatic activity. Another green-revertible albino leaf (gral) mutant involved in chloroplast development was screened from a M2 population induced by 300Gy 60Co gamma rays irradiation to the seeds of rice male sterile line PA64S with the collaboration of Zhejiang University. The mutant seedling leaves exhibit albino firstly but turn to normal green after the sixth leaf extended thoroughly. Systematical research including photosynthetic pigment, chloroplast microscopic observation and gene cloning was carried out on the gral mutant. (author)

  3. Lipoproteins in Drosophila melanogaster--assembly, function, and influence on tissue lipid composition.

    Directory of Open Access Journals (Sweden)

    Wilhelm Palm

    Full Text Available Interorgan lipid transport occurs via lipoproteins, and altered lipoprotein levels correlate with metabolic disease. However, precisely how lipoproteins affect tissue lipid composition has not been comprehensively analyzed. Here, we identify the major lipoproteins of Drosophila melanogaster and use genetics and mass spectrometry to study their assembly, interorgan trafficking, and influence on tissue lipids. The apoB-family lipoprotein Lipophorin (Lpp is the major hemolymph lipid carrier. It is produced as a phospholipid-rich particle by the fat body, and its secretion requires Microsomal Triglyceride Transfer Protein (MTP. Lpp acquires sterols and most diacylglycerol (DAG at the gut via Lipid Transfer Particle (LTP, another fat body-derived apoB-family lipoprotein. The gut, like the fat body, is a lipogenic organ, incorporating both de novo-synthesized and dietary fatty acids into DAG for export. We identify distinct requirements for LTP and Lpp-dependent lipid mobilization in contributing to the neutral and polar lipid composition of the brain and wing imaginal disc. These studies define major routes of interorgan lipid transport in Drosophila and uncover surprising tissue-specific differences in lipoprotein lipid utilization.

  4. Effects of niacin combination therapy with statin or bile acid resin on lipoproteins and cardiovascular disease.

    Science.gov (United States)

    Zambon, Alberto; Zhao, Xue-Qiao; Brown, B Greg; Brunzell, John D

    2014-05-01

    Two large studies in populations selected for cardiovascular disease (CVD) demonstrated that raising high-density lipoprotein (HDL) cholesterol with niacin added to statin therapy did not decrease CVD. We examine the association of lipoprotein subfractions with niacin and changes in coronary stenosis and CVD event risk. One hundred and seven patients from 2 previous studies using niacin in combination with either statin or bile acid-binding resin were selected to evaluate changes in lipoproteins separated by density-gradient ultracentrifugation to progression of coronary artery disease as assessed by quantitative coronary angiography. Improvement in coronary stenosis was significantly associated with the decrease of cholesterol in the dense low-density lipoprotein (LDL) particles and across most of the intermediate density lipoprotein (IDL) and very low density lipoprotein particle density range, but, not with any of the HDL fraction or of the more buoyant LDL fractions. Event-free survival was significantly associated with the decrease of cholesterol in the dense LDL and IDL; there was no association with changes in cholesterol in the HDL and buoyant LDL fractions. Niacin combination therapy raises HDL cholesterol and decreases dense LDL and IDL cholesterol levels. Changes in LDL and IDL are related to improvement in CVD. Lipoprotein subfraction analysis should be performed in larger studies utilizing niacin in combination with statins.

  5. Barley mutant line with high protein yield

    International Nuclear Information System (INIS)

    Mutation breeding was initiated in 1969 at the Agricultural Research Institute, Nicosia, aiming at developing high yielding barley lines having also high protein or lysine content. The final results were reported at the FAO/IAEA Research Co-ordination Meeting at Nicosia in 1980. At that time some lines were superior to their mother line in grain yield, protein content or protein yield. However, high yield is essential for feed-barley as there is no premium price for protein content or quality. In the experiments reported earlier, the mean grain yield of mutant M-Att-73-337-1 was 3202 kg/ha, 9.9% higher than the mother variety 'Attiki'. The Kjeldahl protein content was 12.7% for the mutant line and 13.4% for the mother variety. The mutant line was further evaluated in field trials (11 m2 plots and 6 replications) during 1983-88, along with other promising material from the breeding programme. The mutant line outyielded its mother variety by 9.7% in grain yield and 16% in straw yield. These increases are apparently the result of increased 1000-grain weight and a higher number of culms per m2. Protein content of the mutant line was slightly lower, but its protein yield was 5.5% higher. The yield of the mutant line over 16 trials during 1983-88 was also 4% higher than the yield of the main commercially grown variety Athenais

  6. Crystal structure of the Campylobacter jejuni Cj0090 protein reveals a novel variant of the immunoglobulin fold among bacterial lipoproteins.

    Science.gov (United States)

    Paek, Seonghee; Kawai, Fumihiro; Choi, Kyoung-Jae; Yeo, Hye-Jeong

    2012-12-01

    Bacterial lipoproteins play an important role in bacterial pathogenesis and physiology. The genome of Campylobacter jejuni, a major foodborn pathogen, is predicted to contain over 20 lipoproteins. However, the functions of the majority of C. jejuni lipoproteins remain unknown. The Cj0090 protein is encoded by a lipoprotein operon composed of cj0089, cj0090, and cj0091. Here, we report the crystal structure of Cj0090 at 1.9 Å resolution, revealing a novel variant of the immunoglobulin fold with β-sandwich architecture. The structure suggests that Cj0090 may be involved in protein-protein interactions, consistent with a possible role for bacterial lipoproteins. PMID:22987763

  7. Measurement of cholesterol and other lipoprotein constituents in the clinical laboratory.

    Science.gov (United States)

    Warnick, G R

    2000-04-01

    Measurements of lipids and lipoproteins in the clinical laboratory have become increasingly important because of their predictive association with cardiovascular diseases, especially coronary artery disease. The US National Institutes of Health-sponsored National Cholesterol Education Program and counterparts in other countries have developed national consensus guidelines for diagnosis and treatment of coronary artery disease which provide risk cut-points and define use of the lipid/lipoprotein analytes in case finding and therapy. Total and low density lipoprotein cholesterol and triglycerides are measured as positive risk factors and high density lipoprotein cholesterol as an inverse risk factor for coronary artery disease. A National Cholesterol Education Program-sponsored expert laboratory panel has developed guidelines for measurements with requisite analytical performance targets for total error and corresponding precision and bias. The US Centers for Disease Control and Prevention have established reference methods for total and high density lipoprotein cholesterol and for triglycerides, with a method for low density lipoprotein cholesterol in development. Standardization programs for research laboratories and a Cholesterol Reference Method Laboratory Network for diagnostic manufacturers and clinical laboratories provide reliable access and documentation of traceability to accepted reference methods. Methods for the lipid/lipoprotein analytes have improved dramatically in recent years and, coupled with improved chemistry analyzer systems and more attention to standardization by manufacturers, offer considerable improvement in analytical performance. Fully automated homogeneous assays for high density lipoprotein cholesterol and newer similar assays for low-density lipoprotein cholesterol have potential for better precision as well as more convenient and cost-effective measurements. Attention to pre-analytical sources of variation is also important in making

  8. Apolipoprotein AV Accelerates Plasma Hydrolysis OfTriglyceride-Rich Lipoproteins By Interaction With Proteoglycan BoundLipoprotein Lipase

    Energy Technology Data Exchange (ETDEWEB)

    Merkel, Martin; Loeffler, Britta; Kluger, Malte; Fabig, Nathalie; Geppert, Gesa; Pennacchio, Len A.; Laatsch, Alexander; Heeren, Joerg

    2005-02-22

    Apolipoprotein A5 (APOA5) is associated with differences intriglyceride levels and familial combined hyperlipidemia. In genetically engineered mice, apoAV plasma levels are inversely correlated with plasmatriglycerides. To elucidate the mechanism by which apoAV influences plasma triglycerides, metabolic studies and in vitro assays resembling physiological conditions were performed. In hAPOA5 transgenic mice(hAPOA5tr), catabolism of chylomicrons and VLDL was accelerated due to a faster plasma hydrolysis of triglycerides by lipoprotein lipase (LPL).Hepatic VLDL and intestinal chylomicron production were not affected. The functional interplay between apoAV and LPL was further investigated by crossbreeding a human LPL transgene with the apoa5 knockout, and the hAPOA5tr to an LPL deficient background. Increased LPL activity completely normalized hypertriglyceridemia of apoa5 deficient mice,however, over expression of human apoAV modulated triglyceride levels only slightly when LPL was reduced. To reflect the physiological situation in which LPL is bound to cell surface proteoglycans, we examined hydrolysis in the presence or absence of proteoglycans. Without proteoglycans, apoAV derived either from triglyceride-rich lipoproteins, hAPOA5tr HDL, or a recombinant source did not alter the LPL hydrolysis rate. In the presence of proteoglycans, however, apoAV led to a significant and dose-dependent increase in LPL mediated hydrolysis of VLDL triglycerides. These results were confirmed in cell culture using a proteoglycan-deficient cell line.A direct interaction between LPL and apoAV was found by ligand blotting.It is proposed, that apoAV reduces triglyceride levels by guiding VLDL and chylomicrons to proteoglycans bound LPL for lipolysis.

  9. Low pH-Triggered Beta-Propeller Switch of the Low-Density Lipoprotein Receptor Assists Rhinovirus Infection ▿

    Science.gov (United States)

    Konecsni, Tuende; Berka, Ursula; Pickl-Herk, Angela; Bilek, Gerhard; Khan, Abdul Ghafoor; Gajdzig, Leszek; Fuchs, Renate; Blaas, Dieter

    2009-01-01

    Minor group human rhinoviruses (HRVs) bind three members of the low-density lipoprotein receptor (LDLR) family: LDLR proper, very-LDLR (VLDLR) and LDLR-related protein (LRP). Whereas ICAM-1, the receptor of major group HRVs actively contributes to viral uncoating, LDLRs are rather considered passive vehicles for cargo delivery to the low-pH environment of endosomes. Since the Tyr-Trp-Thr-Asp β-propeller domain of LDLR has been shown to be involved in the dissociation of bound LDL via intramolecular competition at low pH, we studied whether it also plays a role in HRV infection. Human cell lines deficient in LDLR family proteins are not available. Therefore, we used CHO-ldla7 cells that lack endogenous LDLR. These were stably transfected to express either wild-type (wt) human LDLR or a mutant with a deletion of the β-propeller. When HRV2 was attached to the propeller-negative LDLR, a lower pH was required for conversion to subviral particles than when attached to wt LDLR. This indicates that high-avidity receptor binding maintains the virus in its native conformation. HRV2 internalization directed the mutant LDLR but not wt LDLR to lysosomes, resulting in reduced plasma membrane expression of propeller-negative LDLR. Infection assays using a CHO-adapted HRV2 variant showed a delay in intracellular viral conversion and de novo viral synthesis in cells expressing the truncated LDLR. Our data indicate that the β-propeller attenuates the virus-stabilizing effect of LDLR binding and thereby facilitates RNA release from endosomes, resulting in the enhancement of infection. This is a nice example of a virus exploiting high-avidity multimodule receptor binding with an intrinsic release mechanism. PMID:19706701

  10. Obstructive jaundice leads to accumulation of oxidized low density lipoprotein in human liver tissue

    Institute of Scientific and Technical Information of China (English)

    Mustafa Comert; Yucel Ustundag; Ishak Ozel Tekin; Banu Dogan Gun; Figen Barut

    2006-01-01

    Oxidized low density lipoprotein (ox-LDL) molecule is one of the most important modified lipoproteins produced during the oxidative stress. Modified lipoproteins have been defined as being part of the immune inflammatory mechanisms in association with oxidant stress. We have reported the accumulation of ox-LDL in Balb/c mice liver after bile duct ligation previously. Here, we investigated this finding in human beings with obstructive jaundice.Our study demonstrates that obstructive jaundice results in tremendous accumulation of ox-LDL in the liver tissue of patients.

  11. [Lipoproteins HDL and coronary artery disease: a molecular mechanism of fibrate].

    Science.gov (United States)

    Kaletha, Krystian; Chodorowski, Zygmunt; Anand, Izabela Sein; Rybakowska, Iwona; Nagel-Starczynowska, Gabriela

    2003-01-01

    The importance of dyslipidemia in the development of cardiovascular disease is now recognized as a central factor of equal, if not greater significance than any other risk factor. Although correction of high level of low-density lipoproteins (LDL) has been regarded now as the main goal of therapy, it has now been reaffirmed that the contribution of low level of high-density lipoproteins (HDL) to the risk of ischaemic heart disease should also be considered. In the therapy of dislipidemias with hipertriglyceridemia and decreased level of HDL lipoprotein fibrates play an especially important role. In the article the molecular mechanism of fibrates action is presented.

  12. Crystal structures of bacterial lipoprotein localization factors, LolA and LolB

    OpenAIRE

    Takeda, Kazuki; Miyatake, Hideyuki; Yokota, Naoko; Matsuyama, Shin-ichi; Tokuda, Hajime; Miki, Kunio

    2003-01-01

    Lipoproteins having a lipid-modified cysteine at the N-terminus are localized on either the inner or the outer membrane of Escherichia coli depending on the residue at position 2. Five Lol proteins involved in the sorting and membrane localization of lipoprotein are highly conserved in Gram-negative bacteria. We determined the crystal structures of a periplasmic chaperone, LolA, and an outer membrane lipoprotein receptor, LolB. Despite their dissimilar amino acid sequences, the structures of ...

  13. High-density lipoprotein cholesterol on a roller coaster: where will the ride end?

    Science.gov (United States)

    Kronenberg, Florian

    2016-04-01

    Bowe et al. report an association between low high-density lipoprotein cholesterol concentrations and various incident chronic kidney disease end points in a cohort of almost 2 million US veterans followed for 9 years. These impressive data should be a starting point for further investigations including genetic epidemiologic investigations as well as post hoc analyses of interventional trials that target high-density lipoprotein cholesterol and, finally, studies that focus on the functionality of high-density lipoprotein particles. PMID:26994572

  14. Glycosaminoglycan-lipoprotein complexes from aortas of hypercholesterolemic rabbits. Part 1. Isolation and characterization.

    Science.gov (United States)

    Mawhinney, T P; Augustyn, J M; Fritz, K E

    1978-10-01

    Glycosaminoglycan-lipoprotein complexes were isolated from rabbit aortas exhibiting nearly confluent cholesterol-induced foam cell lesions by extraction with 0.15 M NaCl. Purification and characterization was achieved by gel chromatography, non-ionic differential flotation and by cellulose polyacetate electrophoresis. Analysis showed that these complexes consisted of very low density lipoproteins, heparan sulfate, chondroitin sulfate-C and hyaluronic acid. The demonstration that rabbit intimal foam cell lesions contain extractable glycosaminoglycan-lipoprotein complexes makes this animal model an excellent tool for further studies on the role of these complexes in the atherogenic process. PMID:215171

  15. Secretion of bacterial lipoproteins: through the cytoplasmic membrane, the periplasm and beyond.

    Science.gov (United States)

    Zückert, Wolfram R

    2014-08-01

    Bacterial lipoproteins are peripherally anchored membrane proteins that play a variety of roles in bacterial physiology and virulence in monoderm (single membrane-enveloped, e.g., gram-positive) and diderm (double membrane-enveloped, e.g., gram-negative) bacteria. After export of prolipoproteins through the cytoplasmic membrane, which occurs predominantly but not exclusively via the general secretory or Sec pathway, the proteins are lipid-modified at the cytoplasmic membrane in a multistep process that involves sequential modification of a cysteine residue and cleavage of the signal peptide by the signal II peptidase Lsp. In both monoderms and diderms, signal peptide processing is preceded by acylation with a diacylglycerol through preprolipoprotein diacylglycerol transferase (Lgt). In diderms but also some monoderms, lipoproteins are further modified with a third acyl chain through lipoprotein N-acyl transferase (Lnt). Fully modified lipoproteins that are destined to be anchored in the inner leaflet of the outer membrane (OM) are selected, transported and inserted by the Lol (lipoprotein outer membrane localization) pathway machinery, which consists of the inner-membrane (IM) ABC transporter-like LolCDE complex, the periplasmic LolA chaperone and the OM LolB lipoprotein receptor. Retention of lipoproteins in the cytoplasmic membrane results from Lol avoidance signals that were originally described as the "+2 rule". Surface localization of lipoproteins in diderms is rare in most bacteria, with the exception of several spirochetal species. Type 2 (T2SS) and type 5 (T5SS) secretion systems are involved in secretion of specific surface lipoproteins of γ-proteobacteria. In the model spirochete Borrelia burgdorferi, surface lipoprotein secretion does not follow established sorting rules, but remains dependent on N-terminal peptide sequences. Secretion through the outer membrane requires maintenance of lipoproteins in a translocation-competent unfolded conformation

  16. Pituitary progesterone receptor expression and plasma gonadotrophin concentrations in the reproductively dysfunctional mutant restricted ovulator chicken.

    Science.gov (United States)

    Ocón-Grove, Olga M; Maddineni, Sreenivasa; Hendricks, Gilbert L; Elkin, Robert G; Proudman, John A; Ramachandran, Ramesh

    2007-04-01

    Female mutant restricted ovulator (RO) chickens of the White Leghorn strain carry a naturally occurring single nucleotide mutation in the very low density lipoprotein receptor (VLDLR) gene. Due to this mutation, RO hens fail to express a functional VLDLR protein on the oocyte membrane, which results in an impaired uptake of circulating yolk precursor macromolecules. Mutant RO hens subsequently develop hyperlipidemia and generally fail to lay eggs due to follicular atresia. Since RO hens also reportedly have three-fold higher basal plasma estrogen concentrations, combined with four-fold lower levels of circulating progesterone as compared to wild-type (WT) hens, we hypothesized that RO hens would have an increased abundance of pituitary progesterone receptor (PR) mRNA and PR isoforms A and B as well as alterations in circulating gonadotrophin levels. Quantitative PCR assays revealed significantly greater (Pestradiol, but lower circulating progesterone levels. Collectively, elevated circulating estrogen and/or decreased progesterone levels may have contributed to the upregulation of PR mRNA and PR isoforms A and B in the RO hen pituitary gland. Lastly, in order to gain a more complete understanding of why RO hens are reproductively dysfunctional, a model is proposed that links humoral and ovarian factors to observed and putative changes in the hypothalamic-pituitary axis. PMID:16677794

  17. Officially released mutant varieties in China

    International Nuclear Information System (INIS)

    The use of mutation techniques for crop improvement in China has a long and well-established tradition of more than 50 years. As the result of intensive research in many institutes dealing with application of nuclear technologies more than 620 cultivars of 44 crop species have been released. Numerous mutant varieties have been grown on a large scale bringing significant economic impact, sustaining crop production and greatly contributing to increase of food production also in stress prone areas of the country. However, there is still missing information not only on the number of mutant varieties released in particular crop species but also on mutagens applied, selection approaches and on the use of mutants in cross breeding. Numerous Chinese scientists collected and systematized this information. Results of their work were often published in local scientific journals in the Chinese language and as such were unavailable to breeders from other countries. Having this in mind, we requested Dr. Liu Luxiang, the Director of the Department of Plant Mutation Breeding and Genetics, Institute for Application of Atomic Energy, Chinese Academy of Agricultural Sciences in Beijing to help us in finding as much information as possible on mutant varieties officially released in China. The data has been collected in close collaboration with his colleagues from various institutions all over the country and then evaluated, edited and prepared for publication by our team responsible for the FAO/IAEA Database of Officially Released Mutant Varieties. We would like to thank all Chinese colleagues who contributed to this list of Chinese mutant varieties. We hope that this publication will stimulate plant breeders in China to collect more information on released mutant varieties and especially on the use of mutated genes in cross breeding. (author)

  18. [Lipoprotein (a)--a mysterious factor in atherogenesis].

    Science.gov (United States)

    Jelaković, Bojan; Laganović, Mario; Kuzmanić, Dusko

    2002-01-01

    Etiopathogenesis of arterial hypertension and coronary disease involves interaction of numerous exogenous factors which determine the clinical course and therapeutic response in genetically predisposed individuals. The role of numerous cardiovascular risk factors has been reevaluated during the past few years, yet some unresolved issues and gaps still remain. One of the still insufficiently studied factors is lipoprotein (a) [Lp (a)] which belongs to a subclass of LDL lipoproteins. Its important component is apolipoprotein (a) which is structurally similar to plasminogen. This characteristic can be followed through evolution and is probably crucial for its physiologic but also pathophysiologic role. Actually, through its competition with plasminogen, Lp (a) interferes with the process of fibrinolysis and may contribute to tissue healing and restoration but also support and accelerate atherothrombotic process. Lp (a) concentration is stable and genetically determined in an individual and the indication that persons with elevated levels are permanently exposed to increased risk is supported by the data on twofold incidence of myocardial infarction in mothers of children with highest Lp (a) concentrations. Apart from competing with plasminogen via apolipoprotein (a), Lp (a) increases the activity of inhibitors of plasminogen-I activator and reduces the activity of transforming growth factor-beta. This results both in the absence of fibrinolysis and promotion of migration and proliferation of media smooth muscle cells, which are important in the onset of atherosclerotic process. Lp (a) binds to elastin via apolipoprotein B, resulting in oxidation and facilitated entry into macrophages and their transition into the so-called foam cells, also an important sign of early atherosclerosis. Although many pathophysiologic processes by which Lp (a) contributes to atherosclerosis have also been confirmed by animal experiments as well as by the presence of histologic evidence

  19. Role of adipocyte-derived lipoprotein lipase in adipocyte hypertrophy

    Directory of Open Access Journals (Sweden)

    Orlando Robert A

    2007-10-01

    Full Text Available Abstract Background A major portion of available fatty acids for adipocyte uptake is derived from lipoprotein lipase (LPL-mediated hydrolysis of circulating lipoprotein particles. In vivo studies aimed at identifying the precise role of adipocyte-derived LPL in fat storage function of adipose tissue have been unable to provide conclusive evidence due to compensatory mechanisms that activate endogenous fatty acid synthesis. To address this gap in knowledge, we have measured the effect of reducing adipocyte LPL expression on intracellular lipid accumulation using a well-established cultured model of adipocyte differentiation. Methods siRNA specific for mouse LPL was transfected into 3T3-L1 adipocytes. Expression of LPL was measured by quantitative real-time PCR and cell surface-associated LPL enzymatic activity was measured by colorimetric detection following substrate (p-nitrophenyl butyrate hydrolysis. Apolipoprotein CII and CIII expression ratios were also measured by qRT-PCR. Intracellular lipid accumulation was quantified by Nile Red staining. Results During differentiation of 3T3-L1 pre-adipocytes, LPL mRNA expression increases 6-fold resulting in a 2-fold increase in cell surface-associated LPL enzymatic activity. Parallel to this increase in LPL expression, we found that intracellular lipids increased ~10-fold demonstrating a direct correlation between adipocyte-derived LPL expression and lipid storage. We next reduced LPL expression in adipocytes using siRNA transfections to directly quantify the contributions of adipocyte-derived LPL to lipid storage, This treatment reduced LPL mRNA expression and cell surface-associated LPL enzymatic activity to ~50% of non-treated controls while intracellular lipid levels were reduced by 80%. Exogenous addition of purified LPL (to restore extracellular lipolytic activity or palmitate (as a source of free fatty acids to siRNA-treated cells restored intracellular lipid levels to those measured for non

  20. Altered Serum Lipoprotein Profiles in Male and Female Power Lifters Ingesting Anabolic Steroids.

    Science.gov (United States)

    Cohen, Jonathan C.; And Others

    1986-01-01

    Serum lipoprotein profiles were measured in nine male and three female weightlifters who were taking anabolic steroids. The profiles suggest that steriod users may face an increased risk of coronary artery disease. (Author/MT)

  1. Diet and the role of lipoproteins, lipases, and thyroid hormones in coronary lesion growth

    Science.gov (United States)

    Barth, Jacques D.; Jansen, Hans; Reiber, Johan H. C.; Birkenhager, Jan C.; Kromhout, Daan

    1987-01-01

    The relationships between the coronary lesion growth and the blood contents of lipoprotein fractions, thyroic hormones, and the lipoprotein lipase activity were investigated in male patients with severe coronary atherosclerosis, who participated in a lipid-lowering dietary intervention program. A quantitative computer-assisted image-processing technique was used to assess the severity of coronary obstructions at the beginning of the program and at its termination two years later. Based on absolute coronary scores, patients were divided into a no-lesion growth group (14 patients) and a progression group (21 paients). At the end of the trial, the very-low-density lipoprotein cholesterol and triglycerides were found to be significantly higher, while the high-density lipoprotein cholesterol and hepatic lipase (HL) were lower in the progression group. Multivariate regression analysis showed HL to be the most important determinant of changes in coronary atherosclerotic lesions.

  2. Quantitative Lipoproteomics in Clostridium difficile Reveals a Role for Lipoproteins in Sporulation.

    Science.gov (United States)

    Charlton, Thomas M; Kovacs-Simon, Andrea; Michell, Stephen L; Fairweather, Neil F; Tate, Edward W

    2015-11-19

    Bacterial lipoproteins are surface exposed, anchored to the membrane by S-diacylglyceryl modification of the N-terminal cysteine thiol. They play important roles in many essential cellular processes and in bacterial pathogenesis. For example, Clostridium difficile is a Gram-positive anaerobe that causes severe gastrointestinal disease; however, its lipoproteome remains poorly characterized. Here we describe the application of metabolic tagging with alkyne-tagged lipid analogs, in combination with quantitative proteomics, to profile protein lipidation across diverse C. difficile strains and on inactivation of specific components of the lipoprotein biogenesis pathway. These studies provide the first comprehensive map of the C. difficile lipoproteome, demonstrate the existence of two active lipoprotein signal peptidases, and provide insights into lipoprotein function, implicating the lipoproteome in transmission of this pathogen.

  3. Behavioral versus genetic determination of lipoproteins andidentical twins discordant for exercise

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Paul T.; Blanche, Patricia J.; Krauss, Ronald M.

    2004-06-01

    Lipoprotein and weight differences between vigorously active and sedentary MZ twins are used to: (1) estimate the effects of training while controlling for genotype; (2) estimate genetic concordance in the presence of divergent lifestyles.

  4. A novel lipoprotein from the hemolymph of the cochineal insect, Dactylopius confusus.

    Science.gov (United States)

    Ziegler, R; Willingham, L A; Engler, D L; Tolman, K J; Bellows, D; Van Der Horst, D J; Yepiz-Plascencia, G M; Law, J H

    1999-04-01

    A new type of insect lipoprotein was isolated from the hemolymph of the female cochineal insect Dactylopius confusus. The lipoprotein from the cochineal insect hemolymph was found to have a relative molecular mass of 450 000. It contains 48% lipid, mostly diacylglycerol, phospholipids and hydrocarbons. The protein moiety of the lipoprotein consists of two apoproteins of approximately 25 and 22 kDa, both of which are glycosylated. Both apolipoproteins are also found free in the hemolymph, unassociated with any lipid. Purified cochineal apolipoproteins can combine with Manduca sexta lipophorin, if injected together with adipokinetic hormone into M. sexta. This could indicate that the cochineal lipoprotein can function as a lipid shuttle similar to lipophorins of other insects, and that the cochineal insect apolipoproteins have an overall structure similar to insect apolipophorin-III. PMID:10103061

  5. Effects of atorvastatin and simvastatin on low-density lipoprotein subfraction profile, low-density lipoprotein oxidizability, and antibodies to oxidized low-density lipoprotein in relation to carotid intima media thickness in familial hypercholesterolemia.

    NARCIS (Netherlands)

    Tits, L.J.H. van; Smilde, T.J.; Wissen, S. van; Graaf, J. de; Kastelein, J.J.P.; Stalenhoef, A.F.H.

    2004-01-01

    BACKGROUND: Little is known about the effects of statins on the quality of circulating low-density lipoprotein (LDL) in relation to atherosclerosis progression. METHODS: In a double-blind, randomized trial of 325 patients with familial hypercholesterolemia (FH), we assessed the effects of high-dose

  6. Simvastatin but not bezafibrate decreases plasma lipoprotein-associated phospholipase A(2) mass in type 2 diabetes mellitus : Relevance of high sensitive C-reactive protein, lipoprotein profile and low-density lipoprotein (LDL) electronegativity

    NARCIS (Netherlands)

    Constantinides, Alexander; de Vries, Rindert; van Leeuwen, Jeroen J. J.; Gautier, Thomas; van Pelt, L. Joost; Tselepis, Alexandros D.; Lagrost, Laurent; Dullaart, Robin P. F.

    2012-01-01

    Objective: Plasma lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) levels predict incident cardiovascular disease, impacting Lp-PLA(2) as an emerging therapeutic target. We determined Lp-PLA(2) responses to statin and fibrate administration in type 2 diabetes mellitus, and assessed relationship

  7. Preparation and Adsorption Properties of PAM Based Adsorbents for Plasma Lipoproteins

    Institute of Scientific and Technical Information of China (English)

    Hai Tao LI; Zhi YUAN; Xin Fu CHEN; Bin LIU; Bin SHEN; Bing Lin HE

    2004-01-01

    Crosslinked macroporous polyacrylamide(PAM)was prepared with inverse phase suspension polymerization technique.After treatment with hydrazine,the polymer was functionalized with chloroacetic acid,trifluoroacetic acid diethylenetriaminepentaacetic acid (DEPAA), and maleic acid, respectively,and PAM based adsorbents bearing carboxyl functional groups for low density lipoprotein(LDL)apheresis use were obtained.The blood compatibility and the adsorption properties for plasma lipoproteins of PAM based adsorbents were investigated.

  8. Intercorrelations of lipoprotein subfractions and their covariation with lifestyle factors in healthy men

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Eckoldt, J.; Winkler, K.;

    2014-01-01

    So far, little is known about the effect of nutrition and lifestyle on the composition of circulating lipoprotein subfractions. In the current study, we measured the correlations among physical activity, nutrient intake, smoking, body-mass index (BMI), and age with the concentration...... with physical activity, moderate alcohol consumption, and dietary intake of MUFA, which might be exploited in future interventions for prevention of age- and BMI-associated atherogenic shifts of lipoprotein subfractions....

  9. Domain exchange: characterization of a chimeric lipase of hepatic lipase and lipoprotein lipase.

    OpenAIRE

    Wong, H; Davis, R. C.; Nikazy, J; Seebart, K E; Schotz, M C

    1991-01-01

    Hepatic lipase and lipoprotein lipase hydrolyze fatty acids from triacylglycerols and are critical in the metabolism of circulating lipoproteins. The two lipases are similar in size and amino acid sequence but are distinguished by functional differences in substrate preference and cofactor requirement. Presumably, these distinctions result from structural differences in functional domains. To begin localization of these domains, a chimeric lipase was constructed composed of the N-terminal 329...

  10. Measurement of low-density lipoprotein cholesterol in assessment and management of cardiovascular disease risk.

    Science.gov (United States)

    Jialal, I; Remaley, A T

    2014-07-01

    The deposition of cholesterol in the arterial wall by the infiltration of low-density lipoproteins (LDLs) is a key step in the development of atherosclerosis. In this Commentary, we discuss recent recommendations for clinical laboratory measurement of low-density lipoprotein cholesterol (LDL-C) and its utility both for assessing cardiovascular disease risk and as a tool in the management of patients receiving lipid-lowering therapy.

  11. Hypoascorbemia induces atherosclerosis and vascular deposition of lipoprotein(a) in transgenic mice

    OpenAIRE

    Cha, John; NIEDZWIECKI, ALEKSANDRA; RATH, MATTHIAS

    2015-01-01

    Lipoprotein(a), a variant of LDL carrying the adhesive glycoprotein apo(a), is a leading risk factor for cardiovascular disease. Lipoprotein(a) (Lp(a)) is found in humans and subhuman primates but rarely in lower mammals. Better understanding of the evolutionary advantage of this molecule should elucidate its physiological role. We developed a new mouse model with two characteristics of human metabolism: the expression of Lp(a) and the lack of endogenous ascorbate (vitamin C) production. We s...

  12. Amphid defective mutant of Caenorhabditis elegans.

    Science.gov (United States)

    De Riso, L; Ristoratore, F; Sebastiano, M; Bazzicalupo, P

    1994-01-01

    Studies are reported on a chemoreception mutant which arose in a mutator strain. The mutant sensory neurons do not stain with fluoresceine isothiocyanate (Dyf phenotype), hence the name, dyf-1, given to the gene it identifies. The gene maps on LGI, 0.4 map units from dpy-5 on the unc-11 side. The response of mutant worms to various repellents has been studied and shown to be partially altered. Other chemoreception based behaviors are less affected. The cilia of the sensory neurons of the amphid are shorter than normal and the primary defect may be in the capacity of the sheath cells to secrete the matrix material that fills the space between cilia in the amphid channel. Progress toward the molecular cloning of the gene is also reported. Relevant results from other laboratories are briefly reviewed. PMID:7896139

  13. Inhibitory effect of morinda citrifolia L. On lipoprotein lipase activity.

    Science.gov (United States)

    Pak-Dek, M S; Abdul-Hamid, A; Osman, A; Soh, C S

    2008-10-01

    Efficacy of Morinda citrifolia L. leaf (MLE) and fruit extracts (MFE) in inhibiting lipoprotein lipase (LPL) was determined in vitro. The result of the study showed that the highest inhibition on the LPL activity was exhibited by MLE (66%+/- 2.1%), which is significantly higher than that demonstrated by MFE (54.5%+/- 2.5%), green tea extract (GTE) (54.5%+/- 2.6%), and catechin (43.6%+/- 6.1%). Percent of LPL inhibition increase with concentration of the extracts. Quantitative analysis of the extracts revealed the presence of high levels of (+)-catechin at 63.5 +/- 17 and 53.7 +/- 5.7 mg/g in MLE and MFE, respectively, although not as high as that found in GTE (530.6 +/- 42 mg/g). Appreciable amount of epicatechin was found in all extracts tested, while rutin was only found in MLE and MFE. The study suggested that both leaf and fruit of M. citrifolia may be used as antiobesity agents in body weight management.

  14. A novel lipoprotein nanoparticle system for membrane proteins

    Science.gov (United States)

    Frauenfeld, Jens; Löving, Robin; Armache, Jean-Paul; Sonnen, Andreas; Guettou, Fatma; Moberg, Per; Zhu, Lin; Jegerschöld, Caroline; Flayhan, Ali; Briggs, John A.G.; Garoff, Henrik; Löw, Christian; Cheng, Yifan; Nordlund, Pär

    2016-01-01

    Membrane proteins are of outstanding importance in biology, drug discovery and vaccination. A common limiting factor in research and applications involving membrane proteins is the ability to solubilize and stabilize membrane proteins. Although detergents represent the major means for solubilizing membrane proteins, they are often associated with protein instability and poor applicability in structural and biophysical studies. Here, we present a novel lipoprotein nanoparticle system that allows for the reconstitution of membrane proteins into a lipid environment that is stabilized by a scaffold of Saposin proteins. We showcase the applicability of the method on two purified membrane protein complexes as well as the direct solubilization and nanoparticle-incorporation of a viral membrane protein complex from the virus membrane. We also demonstrate that this lipid nanoparticle methodology facilitates high-resolution structural studies of membrane proteins in a lipid environment by single-particle electron cryo-microscopy (cryo-EM) and allows for the stabilization of the HIV-envelope glycoprotein in a functional state. PMID:26950744

  15. Native low density lipoprotein promotes lipid raft formation in macrophages.

    Science.gov (United States)

    Song, Jian; Ping, Ling-Yan; Duong, Duc M; Gao, Xiao-Yan; He, Chun-Yan; Wei, Lei; Wu, Jun-Zhu

    2016-03-01

    Oxidized low‑density lipoprotein (LDL) has an important role in atherogenesis; however, the mechanisms underlying cell‑mediated LDL oxidation remain to be elucidated. The present study investigated whether native‑LDL induced lipid raft formation, in order to gain further insight into LDL oxidation. Confocal microscopic analysis revealed that lipid rafts were aggregated or clustered in the membrane, which were colocalized with myeloperoxidase (MPO) upon native LDL stimulation; however, in the presence of methyl‑β‑cyclodextrin (MβCD), LDL‑stimulated aggregation, translocation, and colocalization of lipid rafts components was abolished.. In addition, lipid raft disruptors MβCD and filipin decreased malondialdehyde expression levels. Density gradient centrifugation coupled to label‑free quantitative proteomic analysis identified 1,449 individual proteins, of which 203 were significantly upregulated following native‑LDL stimulation. Functional classification of the proteins identified in the lipid rafts revealed that the expression levels of translocation proteins were upregulated. In conclusion, the results of the present study indicated that native‑LDL induced lipid raft clustering in macrophages, and the expression levels of several proteins were altered in the stimulated macrophages, which provided novel insights into the mechanism underlying LDL oxidation.

  16. Simulated lipoprotein transport in the wall of branched arteries.

    Science.gov (United States)

    Darbeau, M Z; Lutz, R J; Collins, W E

    2000-01-01

    Study of arterial blood flow dynamics improves our understanding of the development of cardiovascular diseases such as atherosclerosis. The transport and accumulation of macromolecules in the arterial wall can be influenced by local fluid mechanics. We used numeric simulations to investigate such transport in a T-junction model. Presumably an in vitro experiment would consist of gel segments inserted in the walls of a mechanical flow T-junction model near branch points where separation and recirculation zones are expected. The transport of low density lipoprotein (LDL) was investigated theoretically at these sites in a two dimensional numeric T-branch model. In the numeric model, the hydraulic conductivity of the porous gel wall segments was varied for a fixed species diffusivity to provide simulations with wall transmural Peclet numbers ranging from 0.3 to 30. Steady state flow patterns in the lumen of the two dimensional T-branch were simulated at Reynolds numbers of 250 and 500, using the software package FIDAP 7.61 to implement the finite element method. The simulations demonstrated that wall Peclet numbers greater than 1.0 were needed to achieve species concentration gradients within the wall that varied in the axial direction, thereby reflecting the influence of disturbed flow and pressure patterns in the lumen. As expected, the transmural concentration gradients were steeper when convection predominated. Blood flow in the lumen can influence the distribution of macromolecules in the arterial wall and needs to be investigated for the relevance to atherosclerosis.

  17. Lipoprotein particle subclasses, cardiovascular disease and HIV infection

    DEFF Research Database (Denmark)

    Duprez, Daniel A; Kuller, Lewis H; Tracy, Russell;

    2009-01-01

    using conditional logistic models. RESULTS: Total, large and small HDL-p, but not VLDL-p nor LDL-p, were significantly and inversely associated with CVD and its major component, non-fatal coronary heart disease. The HDL-p associations with CVD were reduced after adjustment for high sensitive C...... (viral suppression [VS]). METHODS: In a nested case-control study, lipoprotein particles (p) by nuclear magnetic resonance were measured at baseline and at the visit prior to the CVD event (latest levels) for 248 patients who had a CVD event and for 480 matched controls. Odds ratios (ORs) were estimated......-reactive protein (hsCRP), interleukin-6 (IL-6) and D-dimer. Latest levels of total HDL-p were also significantly inversely associated with CVD; treatment interruption led to decrease of total HDL-p; adjusting for latest HDL-p did not explain the greater risk of CVD that was observed in the DC versus VS group...

  18. Tiliroside and gnaphaliin inhibit human low density lipoprotein oxidation.

    Science.gov (United States)

    Schinella, Guillermo R; Tournier, Horacio A; Máñez, Salvador; de Buschiazzo, Perla M; Del Carmen Recio, María; Ríos, José Luis

    2007-01-01

    Two flavonoids, gnaphaliin and tiliroside, isolated from Helichrysum italicum, were studied in vitro for their capacity to inhibit Cu(2+)-induced human low density lipoprotein (LDL) and diluted plasma oxidation. LDL oxidation was monitored by conjugated diene, thiobarbituric acid-reactive substances (TBARS) formation and electrophoretic mobility on agarose gel. Gnaphaliin and tiliroside increased the lag-phase for diene conjugate production in a dose-dependent manner. The reduction of TBARS production confirmed the antioxidant activity of gnaphaliin and tiliroside with 50% inhibitory concentration (IC(50)) values of 8.0+/-3.9 microM and 7.0+/-2.6 microM respectively. Furthermore, the flavonoids negated the Cu(2+)-induced increase in electrophoretic mobility of LDL. Antioxidant activity of gnaphaliin and tiliroside was significantly different when diluted plasma was oxidised by adding 1 mM CuSO(4). Although both flavonoids again reduced the TBARS production, tiliroside showed higher activity than gnaphaliin (IC(50)=10.6+/-2.5 microM vs. IC(50)>50 microM). In conclusion, tiliroside and gnaphaliin are antioxidants against in vitro Cu(2+)-induced LDL oxidation in the same order of magnitude compared to that of the reference drug, probucol.

  19. Metabolic fate of rat heart endothelial lipoprotein lipase

    International Nuclear Information System (INIS)

    When isolated rat hearts were perfused with medium containing 125I-labeled bovine lipoprotein lipase (LPL), they bound both lipase activity and radioactivity. More than 80% of the bound lipase could be rapidly released by heparin. Low concentrations of bovine LPL displaced 50-60% of the endogeneous, endothelial-bound LPL. Higher concentrations caused additional binding. Both binding and exchange were rapid processes. The hearts continuously released endogenous LPL into the medium. An antiserum that inhibited bovine but not rat LPL was used to differentiate endogeneous and exogeneous LPL activity. When the pool of endothelial LPL was labeled with bovine 125I-labeled LPL and then chased with unlabeled bovine LPL, approximately 50% of the labeled lipase was rapidly displaced. During chase perfusion with medium only, catalytically active bovine LPL appeared in the perfusate. The rate of release was similar to that observed for endogeneous LPL activity and amounted to 10-13% of the heparin-releasable fraction in the first 5 min of perfusion. There was little or no degradation of bovine 125I-labeled LPL to fragments or acid-soluble products. These results indicate that endothelial LPL is accessible for exchange with exogeneous LPL and that detachment rather than degradation may be the pathway for catabolism of endothelial LPL

  20. Lipoprotein(a) and risk of type 2 diabetes

    DEFF Research Database (Denmark)

    Mora, Samia; Kamstrup, Pia R; Rifai, Nader;

    2010-01-01

    BACKGROUND: Previous studies have demonstrated that cardiovascular risk is higher with increased lipoprotein (a) [Lp(a)]. Whether Lp(a) concentration is related to type 2 diabetes is unclear. METHODS: In 26 746 healthy US women (mean age 54.6 years), we prospectively examined baseline Lp......(a) concentrations and incident type 2 diabetes (n = 1670) for a follow-up period of 13 years. We confirmed our findings in 9652 Danish men and women with prevalent diabetes (n = 419). Analyses were adjusted for risk factors that included age, race, smoking, hormone use, family history, blood pressure, body mass...... index, hemoglobin A(1c) (Hb A(1c)), C-reactive protein, and lipids. RESULTS: Lp(a) was inversely associated with incident diabetes, with fully adjusted hazard ratios (HRs) and 95% CIs for quintiles 2-5 vs quintile 1 of 0.87 (0.75-1.01), 0.80 (0.68-0.93), 0.88 (0.76-1.02), and 0.78 (0.67-0.91); P...

  1. Parathyroid hormone is not an inhibitor of lipoprotein lipase activity.

    Science.gov (United States)

    Arnadottir, M; Nilsson-Ehle, P

    1994-01-01

    The reduced lipoprotein lipase (LPL) activities in uraemia are reflected by increased serum triglyceride concentrations and reduced HDL cholesterol concentrations. Both hyperparathyroidism and circulating inhibitor(s) of LPL have been associated with the disturbances of lipid metabolism in uraemia. The aim of the present study was to investigate if parathyroid hormone (PTH) had an inhibitory effect on LPL activity. Plasma post-heparin LPL activities, plasma LPL inhibitory activities, serum PTHintact and serum PTHC-terminal concentrations were analysed in 20 patients on haemodialysis and 20 healthy controls. The effects of purified, human PTHintact and a carboxyterminal fragment of PTH (PTH39-84) on LPL activities in post-heparin plasma from healthy individuals and on the enzyme activity of purified, bovine milk LPL, activated with apolipoprotein CII, were studied. Patients had significantly higher plasma LPL inhibitory activities than controls, but there was no correlation between plasma LPL inhibitory activities and serum PTH concentrations. Neither PTHintact nor PTH39-84 had a significant effect on LPL activities in vitro. Thus there was no evidence of a direct inhibition of LPL activity by PTH under the present in-vivo or in-vitro conditions. PMID:7870347

  2. Lipoprotein(a: Cellular Effects and Molecular Mechanisms

    Directory of Open Access Journals (Sweden)

    Kirsten Riches

    2012-01-01

    Full Text Available Lipoprotein(a (Lp(a is an independent risk factor for the development of cardiovascular disease (CVD. Indeed, individuals with plasma concentrations >20 mg/dL carry a 2-fold increased risk of developing CVD, accounting for ~25% of the population. Circulating levels of Lp(a are remarkably resistant to common lipid lowering therapies, and there are currently no robust treatments available for reduction of Lp(a apart from plasma apheresis, which is costly and labour intensive. The Lp(a molecule is composed of two parts, an LDL/apoB-100 core and a unique glycoprotein, apolipoprotein(a (apo(a, both of which can interact with components of the coagulation cascade, inflammatory pathways, and cells of the blood vessel wall (smooth muscle cells (SMC and endothelial cells (EC. Therefore, it is of key importance to determine the molecular pathways by which Lp(a exerts its influence on the vascular system in order to design therapeutics to target its cellular effects. This paper will summarise the role of Lp(a in modulating cell behaviour in all aspects of the vascular system including platelets, monocytes, SMC, and EC.

  3. JCL roundtable: Lessons from genetic variants altering lipoprotein metabolism.

    Science.gov (United States)

    Brown, William Virgil; Ference, Brian A; Kathiresan, Sekar

    2016-01-01

    Because the Human Genome Project reached its first major milestone in completing the full sequence of human DNA, many new discoveries have been made relating genetic variants to disease. The new methodology that allows much more rapid and focused analyses of selected genes and the ability to screen the entire exome of any individual has provided tools to examine literally thousands of individuals for a given study. Genetic analysis has become a large-scale epidemiologic tool for examining variants in gene structure and correlating them with phenotypic markers of human disorders. These genome-wide association studies have been quite revealing about the mechanism of disorders of many types. These tools have been applied to the appearance of clinical atherosclerosis and to the chronic metabolic risk factors for this disease process. We are joined by 2 individuals who have made very significant contributions to this area of research: Dr Brian Ference of Wayne State University School of Medicine and Dr Sekar Kathiresan from Massachusetts General Hospital and Harvard Medical School. In our discussion, we are going to focus on genetic variants, which lead to changes in lipoprotein concentrations and those that have an association with earlier onset of clinical vascular disease. This roundtable was recorded during the November 2016 American Heart Association Scientific Sessions in Orlando, Florida. PMID:27206929

  4. Low fasting low high-density lipoprotein and postprandial lipemia

    Directory of Open Access Journals (Sweden)

    Sorodila Konstandina

    2004-07-01

    Full Text Available Abstract Background Low levels of high density lipoprotein (HDL cholesterol and disturbed postprandial lipemia are associated with coronary heart disease. In the present study, we evaluated the variation of triglyceride (TG postprandially in respect to serum HDL cholesterol levels. Results Fifty two Greek men were divided into 2 main groups: a the low HDL group (HDL p = 0.002. The low HDL group had significantly higher TG at 4, 6 and 8 h postprandially compared to the controls (p = 0.006, p = 0.002, and p p = 0.017 compared to the matched-control group. ROC analysis showed that fasting TG ≥ 121 mg/dl have 100% sensitivity and 81% specificity for an abnormal TG response (auc = 0.962, p Conclusions The delayed TG clearance postprandially seems to result in low HDL cholesterol even in subjects with low fasting TG. The fasting TG > 121 mg/dl are predictable for abnormal response to fatty meal.

  5. Expression and Identification of Mycoplasma penetrans P35 Lipoprotein

    Institute of Scientific and Technical Information of China (English)

    朱翠明; 吴移谋; 万艳平; 余敏君

    2004-01-01

    Objective: To study the biological activity of Mycoplasma penetrans 35kDa lipoprotein(P35) in vitro, prokaryotic expression vector pQE31/p35 was constructed and recombinant fusion protein P35 (rP35) was expressed in E.coli. Methods: The p35 gene was amplified by polymerase chain reaction(PCR), cloned to pQE31, and a positive clone was screened. PCR-mediated mutagenesis was used to change the two "TGA" triplets to "TGG" triplets within the p35 gene. Production of the recombinant protein was induced by the addition of IPTG to the E.coli culture, rP35 was purified with a Ni-NTA Spin Kit and rP35 purification was analyzed by Western blot. Results: About 1Kb PCR amplification was cloned into pQE31. The two "TGA" triplets within the p35 gene were successfully changed to "TGG" triplets. The pQE31/p35 vector expressed a protein with a calculated molecular mass of 37.4kDa in E.coli. Western blot indicated the 37.4kDa protein was rP35. Conclusion: PQE311p35, a prokaryotic expression vector containing p35 gene, was successfully constructed and expressed in E.coli.

  6. Cardiomyocyte-endothelial cell control of lipoprotein lipase.

    Science.gov (United States)

    Chiu, Amy Pei-Ling; Wan, Andrea; Rodrigues, Brian

    2016-10-01

    In people with diabetes, inadequate pharmaceutical management predisposes the patient to heart failure, which is the leading cause of diabetes related death. One instigator for this cardiac dysfunction is change in fuel utilization by the heart. Thus, following diabetes, when cardiac glucose utilization is impaired, the heart undergoes metabolic transformation wherein it switches to using fats as an exclusive source of energy. Although this switching is geared to help the heart initially, in the long term, this has detrimental effects on cardiac function. These include the generation of noxious byproducts, which damage the cardiomyocytes, and ultimately result in increased morbidity and mortality. A key perpetrator that may be responsible for organizing this metabolic disequilibrium is lipoprotein lipase (LPL), the enzyme responsible for providing fat to the hearts. Either exaggeration or reduction in its activity following diabetes could lead to heart dysfunction. Given the disturbing news that diabetes is rampant across the globe, gaining more insight into the mechanism(s) by which cardiac LPL is regulated may assist other researchers in devising new therapeutic strategies to restore metabolic equilibrium, to help prevent or delay heart disease seen during diabetes. This article is part of a Special Issue entitled: Heart Lipid Metabolism edited by G.D. Lopaschuk. PMID:26995461

  7. Lipoprotein(a) accelerates atherosclerosis in uremic mice

    DEFF Research Database (Denmark)

    Pedersen, Tanja X; McCormick, Sally P; Tsimikas, Sotirios;

    2010-01-01

    lipoprotein-associated OxPL. Thus, Lp(a) may be particularly atherogenic in a uremic setting. We therefore investigated whether transgenic (Tg) expression of human Lp(a) increases atherosclerosis in uremic mice. Moderate uremia was induced by 5/6 nephrectomy (NX) in Tg mice with expression of human apo(a) (n...... = 19), human apoB-100 (n = 20), or human apo(a) + human apoB [Lp(a)] (n = 15), and in wild-type (WT) controls (n = 21). The uremic mice received a high-fat diet, and aortic atherosclerosis was examined 35 weeks later. LDL-cholesterol was increased in apoB-Tg and Lp(a)-Tg mice, but it was normal in apo...... with both apo(a) and Lp(a). In conclusion, expression of apo(a) or Lp(a) increased uremia-induced atherosclerosis. Binding of OxPL on apo(a) and Lp(a) may contribute to the atherogenicity of Lp(a) in uremia....

  8. High-density lipoprotein endocytosis in endothelial cells

    Institute of Scientific and Technical Information of China (English)

    Stefanie; Fruhwürth; Margit; Pavelka; Robert; Bittman; Werner; J; Kovacs; Katharina; M; Walter; Clemens; Rhrl; Herbert; Stangl

    2013-01-01

    AIM: To describe the way stations of high-density lipoprotein(HDL) uptake and its lipid exchange in endothelial cells in vitro and in vivo. METHODS: A combination of fluorescence microscopy using novel fluorescent cholesterol surrogates and electron microscopy was used to analyze HDL endocytosis in great detail in primary human endothelial cells. Further, HDL uptake was quantified using radio-labeled HDL particles. To validate the in vitro findings mice were injected with fluorescently labeled HDL and particle uptake in the liver was analyzed using fluorescencemicroscopy. RESULTS: HDL uptake occurred via clathrin-coated pits, tubular endosomes and multivesicular bodies in human umbilical vein endothelial cells. During uptake and resecretion, HDL-derived cholesterol was exchanged at a faster rate than cholesteryl oleate, resembling the HDL particle pathway seen in hepatic cells. In addition, lysosomes were not involved in this process and thus HDL degradation was not detectable. In vivo, we found HDL mainly localized in mouse hepatic endothelial cells. HDL was not detected in parenchymal liver cells, indicating that lipid transfer from HDL to hepatocytes occurs primarily via scavenger receptor, class B, type Ⅰ mediated selective uptake without concomitant HDL endocytosis. CONCLUSION: HDL endocytosis occurs via clathrincoated pits, tubular endosomes and multivesicular bodies in human endothelial cells. Mouse endothelial cells showed a similar HDL uptake pattern in vivo indicating that the endothelium is one major site of HDL endocytosis and transcytosis.

  9. Specific pools of phospholipids are used for lipoprotein secretion by cultured rat hepatocytes

    International Nuclear Information System (INIS)

    The role of phospholipid biosynthesis in lipoprotein secretion from cultured rat hepatocytes has been investigated. In liver, phosphatidylcholine (PC) is made both by the CDP-choline pathway and by the methylation of phosphatidyl-ethanolamine (PE), which in turn is derived from both serine (via phosphatidylserine) and ethanolamine (via CDP-ethanol-amine). Monolayer cultures of rat hepatocytes were incubated in the presence of [methyl-3H]choline, [2-3H]ethanolamine or [3-3H]serine. The specific radioactivity of the phospholipids derived from each of these precursors was measured in the cells and in the secreted lipoproteins of the culture medium. The specific radioactivities of PC and PE derived from [1-3H]ethanolamine were markedly lower (approximately 1/2 and less than 1/10, respectively) in the secreted phospholipids than in the cellular phospholipids. Thus, ethanolamine was not an effective precursor of the phospholipids in lipoproteins. On the contrary, the specific radioactivity of PC made from [methyl-3H]choline was approximately equal in cells and lipoproteins. In addition, over the first 4 h of incubation with [3-3H]serine, the specific radioactivities of PC and PE were significantly higher in the lipoproteins than in the cells. These data indicate that specific pools of phospholipids are selected on the basis of their routes of biosynthesis, for secretion into lipoproteins

  10. Lycopene stabilizes lipoprotein levels during D-galactosamine/lipopolysaccharide induced hepatitis in experimental rats

    Institute of Scientific and Technical Information of China (English)

    Sheik Abdulazeez Sheriff; Thiruvengadam Devaki

    2012-01-01

    Objective: To investigate the effect of lycopene on lipoprotein metabolism during D-galactosamine/lipopolysaccharide (D-Gal/LPS) induced hepatitis in experimental rats. Methods: The efficacy of lycopene was validated during D-Gal/LPS induced hepatitis by analyzing the activity of lipid metabolizing enzymes such as lipoprotein lipase (LPL), lecithin-cholesterol acyl transferase (LCAT) and hepatic triglyceride lipase (HTGL). Lipo protein analyses were done by the estimation of very low density lipoprotein cholesterol (VLDL), low density lipoprotein cholesterol (LDL) and high density lipoprotein cholesterol (HDL). Results: The toxic insult of D-galactosamine/lipopolysaccharide (D-Gal/LPS) in experimental group of animals reduces the normal values of lipid metabolizing enzymes due to liver injury. The significant drop in the levels of HDL and concomitant increase in the values of VLDL and LDL were observed. The pretreatment of lycopene restore these altered values to near normal level in experimental group of animals. Conclusions: In the light of results, it can be concluded that administration lycopene stabilizes the lipoprotein levels by regulating the lipid metabolizing enzymes through its antioxidant defense and helps to maintain the normal lipid metabolism during toxic injury in liver.

  11. Lipoprotein Abnormalities in Cholestasis I. Electro-phoretic and Ultracentrifugal Analyses

    Directory of Open Access Journals (Sweden)

    Watanabe,Makoto

    1979-08-01

    Full Text Available The alterations of lipid composition in sera of patients with liver diseases, particularly intrahepatic cholestasis and biliary obstruction, were studied by ultracentrifugation and polyacrylamide-gel disc-electrophoresis of lipoproteins and apoproteins. The elevation of serum cholesterol in intrahepatic cholestasis was greater than in biliary obstruction. The appearance of lipoprotein X in obstructive disease accounted for most of the increased cholesterol. The level of non-lipoprotein X cholesterol in intrahepatic cholestasis was significantly elevated, this being in part ascribed to the appearance of a new class of cholestatic lipoprotein, Slow-migrating HDL. The electrophoretic pattern of lipoprotein in cholestasis was generally characterized by a decrease in alpha band intensity and, in some types of cholestasis, by the appearance of Slow-migrating HDL. In addition, other abnormal lipoproteins exhibiting the characteristics of triglyceride-rich LDL (LP-Y, LP-X-like HDL and LDL-like HDL were found in some cases of intrahepatic cholestasis and biliary obstruction.

  12. Aging Kit mutant mice develop cardiomyopathy.

    Directory of Open Access Journals (Sweden)

    Lei Ye

    Full Text Available Both bone marrow (BM and myocardium contain progenitor cells expressing the c-Kit tyrosine kinase. The aims of this study were to determine the effects of c-Kit mutations on: i. myocardial c-Kit(+ cells counts and ii. the stability of left ventricular (LV contractile function and structure during aging. LV structure and contractile function were evaluated (echocardiography in two groups of Kit mutant (W/Wv and W41/W42 and in wild type (WT mice at 4 and 12 months of age and the effects of the mutations on LV mass, vascular density and the numbers of proliferating cells were also determined. In 4 month old Kit mutant and WT mice, LV ejection fractions (EF and LV fractional shortening rates (FS were comparable. At 12 months of age EF and FS were significantly decreased and LV mass was significantly increased only in W41/W42 mice. Myocardial vascular densities and c-Kit(+ cell numbers were significantly reduced in both mutant groups when compared to WT hearts. Replacement of mutant BM with WT BM at 4 months of age did not prevent these abnormalities in either mutant group although they were somewhat attenuated in the W/Wv group. Notably BM transplantation did not prevent the development of cardiomyopathy in 12 month W41/W42 mice. The data suggest that decreased numbers and functional capacities of c-Kit(+ cardiac resident progenitor cells may be the basis of the cardiomyopathy in W41/W42 mice and although defects in mutant BM progenitor cells may prove to be contributory, they are not causal.

  13. Behavioral characterization of system xc- mutant mice.

    Science.gov (United States)

    McCullagh, Elizabeth A; Featherstone, David E

    2014-05-15

    The slc7a11 gene encodes xCT, an essential component of 'system xc-', a plasma membrane exchanger that imports cystine and exports glutamate. Slc7a11 is expressed primarily in the brain, but its role there is not clear. We performed behavioral tests on two different strains of homozygous slc7a11 mutant mice ('sut' and 'xCT'), as well as heteroallelic offspring of these two strains ('xCT/sut') and their associated genetic backgrounds. Homozygous sut mutant males showed reduced spontaneous alternation in spontaneous alternation tasks as well as reduced movement in an open field maze, but xCT and xCT/sut strains did not show significant changes in these tasks compared to appropriate controls. Neither xCT nor sut mutants showed differences from controls in rotarod tests. Female behavioral phenotypes were independent of estrus cycle stage. To ensure that homozygous xCT, sut, and xCT/sut strains all represent protein null alleles, we measured whole brain xCT protein levels using immunoblots. xCT, sut and xCT/sut strains showed no detectable xCT protein expression, confirming them as null alleles. Previously published microdialysis experiments showed reduced striatal glutamate in xCT mutants. Using the same methods, we measured reduced interstitial glutamate levels in the striatum but not cerebellum of sut mutants. However, we detected no glutamate change in the striatum or cerebellum of sut/xCT mice. We detected no changes in whole brain EAAT-1, -2, or -3 expression. We conclude that the behavioral and chemical differences exist between slc7a11 mutant strains, but we were unable to definitively attribute any of these differences to loss of system xc-.

  14. Effect of apolipoprotein M on high density lipoprotein metabolism and atherosclerosis in low density lipoprotein receptor knock-out mice

    DEFF Research Database (Denmark)

    Christoffersen, Christina; Jauhiainen, Matti; Moser, Markus;

    2008-01-01

    To investigate the role of apoM in high density lipoprotein (HDL) metabolism and atherogenesis, we generated human apoM transgenic (apoM-Tg) and apoM-deficient (apoM(-/-)) mice. Plasma apoM was predominantly associated with 10-12-nm alpha-migrating HDL particles. Human apoM overexpression (11-fold......) increased plasma cholesterol concentration by 13-22%, whereas apoM deficiency decreased it by 17-21%. The size and charge of apoA-I-containing HDL in plasma were not changed in apoM-Tg or apoM(-/-) mice. However, in plasma incubated at 37 degrees C, lecithin:cholesterol acyltransferase-dependent conversion...... of alpha- to pre-alpha-migrating HDL was delayed in apoM-Tg mice. Moreover, lecithin: cholesterol acyltransferase-independent generation of pre-beta-migrating apoA-I-containing particles in plasma was increased in apoM-Tg mice (4.2 +/- 1.1%, p = 0.06) and decreased in apoM(-/-) mice (0.5 +/- 0.3%, p = 0...

  15. A 90 minute soccer match decreases triglyceride and low density lipoprotein but not high-density lipoprotein and cholesterol levels

    Directory of Open Access Journals (Sweden)

    Nader - Rahnama

    2009-11-01

    Full Text Available

    • BACKGROUND: The association between the lipid profiles level and the incidence and severity of coronary heart disease (CHD is very pronounced in epidemiological studies, and an inverse relation between physical fitness and the incidence of coronary heart disease has been observed in many studies. The aim of this study was to investigate the impact of a soccer match on lipid parameters of professional soccer players.
    • METHODS: Twenty two professional soccer players participated in the study. Blood (10ml for determination of lipid profiles was obtained at rest and immediately after a 90 minute soccer match. Lipid parameters were measured using Boehringer Mannheim kits and Clinilab and BioMerieux analyser.
    • RESULTS: The results of this study showed that the triglyceride was significantly higher before the match than afterwards (159.09 ± 58.2 vs. 88.63 ± 34.1 mg/dl, p < 0.001, whereas the low-density lipoprotein (LDL was lower before the match than after it (98.04 ± 28.9 vs. 112.31 ± 30.5 mg/dl. Moreover, there were no significant differences in cholesterol concentration (171.4 ± 30.28 mg/dl vs. 173.18 ± 32.75 mg/dl and high-density lipoprotein (HDL concentration (34.04 ± 5.58 mg/dl vs. 34.4 ± 4.6 mg/dl between before and after the match.
    • CONCLUSIONS: Although the soccer competitive match has no favourable acute effect on lipid

    • Association of polymorphisms in genes involved in lipoprotein metabolism with plasma concentrations of remnant lipoproteins and HDL subpopulations before and after hormone therapy in postmenopausal women

      Science.gov (United States)

      Diabetes mellitus is a major risk factor for coronary heart disease (CHD), renal failure, retinopathy, and neuropathy. Lowering glycosylated hemoglobin (HbA1c) as well as low-density lipoprotein-cholesterol (LDL-C) has been associated with a decreased risk of these complications. We evaluated the ut...

    • Different effects of diets rich in olive oil, rapeseed oil and sunflower-seed oil on postprandial lipid and lipoprotein concentrations and on lipoprotein oxidation susceptibility

      DEFF Research Database (Denmark)

      Nielsen, Nina Skall; Pedersen, A.; Sandstrøm, B.;

      2002-01-01

      oxidation of fasting and postprandial lipoproteins eighteen males consumed diets enriched with rapeseed oil (RO), olive oil (OO), or sunflower-seed oil (SO) in randomised order for periods of 3 weeks followed by a RO test meal. In the postprandial state the concentrations of cholesterol and triacylglycerol...

    • Molecular Genetic Identification Of Some Flax Mutants

      International Nuclear Information System (INIS)

      Five flax genotypes (Linum usitatissimum L.) i.e., commercial cultivar Sakha 2, the mother variety Giza 4 and three mutant types induced by gamma rays, were screened for their salinity tolerance in field experiments (salinity concentration was 8600 and 8300 ppm for soil and irrigation water, respectively). Mutation 6 was the most salt tolerant as compared to the other four genotypes.RAPD technique was used to detect some molecular markers associated with salt tolerance in flax (Mut 6), RAPD-PCR results using 12 random primers exhibited 149 amplified fragments; 91.9% of them were polymorphic and twelve molecular markers (8.1%) for salt tolerant (mutant 6) were identified with molecular size ranged from 191 to 4159 bp and only eight primers successes to amplify these specific markers. Concerning the other mutants, Mut 15 and Mut 25 exhibited 4.3% and 16.2% specific markers, respectively. The induced mutants exhibited genetic similarity to the parent variety were about 51%, 58.3% and 61.1% for Mut 25, Mut 6 and Mut 15, respectively. These specific markers (SM) are used for identification of the induced mutations and it is important for new variety registration.

    • Straight Mutants of Spirillum volutans Can Swim

      OpenAIRE

      Padgett, P. J.; Friedman, M. W.; Krieg, N R

      1983-01-01

      Nonhelical mutant cells of Spirillum volutans ATCC 19554 can swim as fast as the helical cells. Consequently, a helical cell shape is not required for motility of this species, and the function of the polar flagellar fascicles is not merely to cause rotation, and therefore translocation, of the corkscrew-shaped cell.

    • A dominant semi dwarf mutant in rice

      Institute of Scientific and Technical Information of China (English)

      2002-01-01

      @@ In the winter of 1997, a semi dwarf mutant was found in the F6 population of M9056/ R8018 xuan in Hainan Province. In the spring of 1998, the seeds were sown in Hefei, Anhui Province and the plant height of the population was measured at maturity.

  1. Induced mutants for cereal grain protein improvement

    International Nuclear Information System (INIS)

    Out of 17 papers and one summary presented, six dealing with the genetic improvement of seed protein using ionizing radiations fall within the INIS subject scope. Other topics discussed were non-radiation induced mutants used for cereal grain protein improvement

  2. High-density lipoprotein and atherosclerosis: Roles of lipid transporters

    Institute of Scientific and Technical Information of China (English)

    Yoshinari; Uehara; Keijiro; Saku

    2014-01-01

    Various previous studies have found a negative cor-relation between the risk of cardiovascular events and serum high-density lipoprotein(HDL) cholesterol levels. The reverse cholesterol transport, a pathway of choles-terol from peripheral tissue to liver which has several potent antiatherogenic properties. For instance, the particles of HDL mediate to transport cholesterol from cells in arterial tissues, particularly from atherosclerotic plaques, to the liver. Both ATP-binding cassette trans-porters(ABC) A1 and ABCG1 are membrane cholesterol transporters and have been implicated in mediating cholesterol effluxes from cells in the presence of HDL and apolipoprotein A-I, a major protein constituent of HDL. Previous studies demonstrated that ABCA1 and ABCG1 or the interaction between ABCA1 and ABCG1 exerted antiatherosclerotic effects. As a therapeutic approach for increasing HDL cholesterol levels, much focus has been placed on increasing HDL cholesterol levels as well as enhancing HDL biochemical functions. HDL therapies that use injections of reconstituted HDL, apoA-I mimetics, or full-length apoA-I have shown dramatic effectiveness. In particular, a novel apoA-I mi-metic peptide, Fukuoka University ApoA-I Mimetic Pep-tide, effectively removes cholesterol via specific ABCA1 and other transporters, such as ABCG1, and has an an-tiatherosclerotic effect by enhancing the biological func-tions of HDL without changing circulating HDL choles-terol levels. Thus, HDL-targeting therapy has significant atheroprotective potential, as it uses lipid transporter-targeting agents, and may prove to be a therapeutic tool for atherosclerotic cardiovascular diseases.

  3. Biomimetic High-Density Lipoproteins from a Gold Nanoparticle Template

    Science.gov (United States)

    Luthi, Andrea Jane

    For hundreds of years the field of chemistry has looked to nature for inspiration and insight to develop novel solutions for the treatment of human diseases. The ability of chemists to identify, mimic, and modifiy small molecules found in nature has led to the discovery and development of many important therapeutics. Chemistry on the nanoscale has made it possible to mimic natural, macromolecular structures that may also be useful for understanding and treating diseases. One example of such a structure is high-density lipoprotein (HDL). The goal of this work is to use a gold nanoparticle (Au NP) as a template to synthesize functional mimics of HDL and characterize their structure and function. Chapter 1 details the structure and function of natural HDL and how chemistry on the nanoscale provides new strategies for mimicking HDL. This Chapter also describes the first examples of using nanoparticles to mimic HDL. Chapter 2 reports the synthesis and characterization of biomimetic HDL using different sizes of Au NPs and different surface chemistries and how these variables can be used to tailor the properties of biomimetic HDL. From these studies the optimal strategy for synthesizing biomimetic HDL was determined. In Chapter 3, the optimization of the synthesis of biomimetic HDL is discussed as well as a full characterization of its structure. In addition, the work in this chapter shows that biomimetic HDL can be synthesized on a large scale without alterations to its structure or function. Chapter 4 focuses on understanding the pathways by which biomimetic HDL accepts cholesterol from macrophage cells. The results of these studies demonstrate that biomimetic HDL is able to accept cholesterol by both active and passive pathways of cholesterol efflux. In Chapter 5 the preliminary results of in vivo studies to characterize the pharmacokinetics and pharmacodynamics of biomimetic HDL are presented. These studies suggest that biomimetic HDL traffics through tissues prone to

  4. Ethnicity and lipoprotein(a) polymorphism in Native Mexican populations

    Science.gov (United States)

    Cardoso-Saldaña, Guillermo; De La Peña-Díaz, Aurora; Zamora-González, José; Gomez-Ortega, Rocio; Posadas-Romero, Carlos; Izaguirre-Avila, Raul; Malvido-Miranda, Elsa; Morales-Anduaga, Maria Elena; Angles-Cano, Eduardo

    2006-01-01

    Background Lp(a) is a lipoparticle of unknown function mainly present in primates and humans. It consists of a low-density lipoprotein and apo(a), a polymorphic glycoprotein. Apo(a) shares sequence homology and fibrin-binding with plasminogen inhibiting its fibrinolytic properties. Lp(a) is considered a link between atherosclerosis and thrombosis. Marked inter-ethnic differences in Lp(a) concentration related to the genetic polymorphism of apo(a), have been reported in several populations. Aim To study the structural and functional features of Lp(a) in three Native Mexican populations (Mayos, Mazahuas and Mayas) and in Mestizo subjects. Methods We determined the plasma concentration of Lp(a) by immunonephelometry, apo(a) isoforms by Western blot, Lp(a) fibrin-binding by immuno-enzymatic assay and STR polymorphic markers genetic analysis by capillary electrophoresis. Results Mestizos presented the less skewed distribution and the highest median Lp(a) concentration (13.25 mg/dL) relative to Mazahuas (8.2 mg/dL), Mayas (8.25 mg/dL) and Mayos (6.5 mg/dL). Phenotype distribution was different in Mayas and Mazahuas as compared to the Mestizo group. The higher Lp(a) fibrin-binding capacity was found in the Maya population. There was an inverse relationship between the size of apo(a) polymorphs and both Lp(a) levels and Lp(a) fibrin binding. Conclusion There is evidence of significative differences in Lp(a) plasma concentration and phenotype distribution in Native Mexican and the Mestizo group. PMID:16684693

  5. Reconstituted high-density lipoprotein modulates activation of human leukocytes.

    Directory of Open Access Journals (Sweden)

    Rolf Spirig

    Full Text Available An anti-inflammatory effect of reconstituted High Density Lipoprotein (rHDL has been demonstrated in atherosclerosis and in sepsis models. An increase of adhesion molecules as well as tissue factor expression on endothelial cells in response to inflammatory or danger signals are attenuated by the treatment with rHDL. Here we show the inhibitory effect of rHDL on the activation of human leukocytes in a whole blood assay as well as on monocyte-derived human dendritic cells (DC. Multiplex analysis of human whole blood showed that phytohaemagglutinin (PHA-induced secretion of the cytokines IL-1β, IL-1RA, IL-2R, IL-6, IL-7, IL-12(p40, IL-15 and IFN-α was inhibited. Furthermore, an inhibitory effect on the production of the chemokines CCL-2, CCL-4, CCL-5, CXCL-9 and CXCL-10 was observed. Activation of granulocytes and CD14+ monocytes by PHA is inhibited dose-dependently by rHDL shown as decreased up-regulation of ICAM-1 surface expression. In addition, we found a strong inhibitory effect of rHDL on toll-like receptor 2 (TLR2- and TLR4-mediated maturation of DC. Treatment of DC with rHDL prevented the up-regulation of cell surface molecules CD80, CD83 and CD86 and it inhibited the TLR-driven activation of inflammatory transcription factor NF-κB. These findings suggest that rHDL prevents activation of crucial cellular players of cellular immunity and could therefore be a useful reagent to impede inflammation as well as the link between innate and adaptive immunity.

  6. Impact of lipoprotein lipase gene polymorphisms on ulcerative colitis

    Institute of Scientific and Technical Information of China (English)

    Toshihito Kosaka; Taizou Shiraishi; Masatoshi Watanabe; Takayuki Yamamoto; Ai Nakahara; Takahiko Katoh; Junji Yoshino; Kazuo Inui; Takao Wakabayashi; Kazumu Okushima; Takashi Kobayashi; Hironao Miyoshi; Yuta Nakamura; Shigekazu Hayashi

    2006-01-01

    AIM: To examine the influence of lipoprotein lipase (LPL)gene polymorphism in ulcerative colitis (UC) patients.METHODS: Peripheral blood was obtained from 131 patients with UC and 106 healthy controls for DNA extraction. We determined LPL gene polymorphisms affecting the enzyme at Ser447stop, as well as Hind Ⅲ and Pvu Ⅱ polymorphisms using PCR techniques. PCR products were characterized by PCR-RFLP and direct sequencing.Polymorphisms were examined for association with clinical features in UC patients. Genotype frequencies for LPL polymorphisms were also compared between UC patients and controls.RESULTS: In patients with onset at age 20 years or younger, C/G and G/G genotypes for Ser447stop polymorphism were more prevalent than C/C genotype (OR= 3.13, 95% CI = 0.95-10.33). Patients with H+/- or H-/-genotype for HindⅢ polymorphism also were more numerous than those with H+/+ genotype (OR = 2.51, 95%CI = 0.85-7.45). In the group with H+/+ genotype for HindⅢ polymorphism, more patients had serum triglyceride concentrations over 150 mg/dL than patients with H+/- or H-/- genotype (P < 0.01, OR = 6.46, 95% CI =1.39-30.12). Hypertriglycemia was also more prevalent in patients with P+/+ genotypes for Pvu Ⅱ polymorphism (P< 0.05, OR = 3.0, 95% CI = 1.06-8.50). Genotype frequency for LPL polymorphism did not differ significantly between UC patients and controls.CONCLUSION: Ser447stop and HindⅢ LPL polymorphisms may influence age of onset of UC, while HindⅢand PvuⅡ polymorphisms influence serum triglyceride in UC patients.

  7. Lipid composition of circulating multiple-modified low density lipoprotein.

    Science.gov (United States)

    Zakiev, E R; Sukhorukov, V N; Melnichenko, A A; Sobenin, I A; Ivanova, E A; Orekhov, A N

    2016-01-01

    Atherogenic modified low- density lipoprotein (LDL) induces pronounced accumulation of cholesterol and lipids in the arterial wall, while native LDL seems to lack such capability. Therefore, modified LDL appears to be a major causative agent in the pathogenesis of atherosclerosis. Possible modifications of LDL particles include changes in size and density, desialylation, oxidation and acquisition of negative charge. Total LDL isolated from pooled plasma of patients with coronary atherosclerosis, as well as from healthy subjects contains two distinct subfractions: normally sialylated LDL and desialylated LDL, which can be isolated by binding to a lectin affinity column. We called the desialylated LDL subfraction circulating modified LDL (cmLDL). In this study, we focused on lipid composition of LDL particles, analysing the total LDL preparation and two LDL subfractions: cmLDL and native LDL. The composition of LDL was studied using thin-layer chromatography. We found that cmLDL subfraction had decreased levels of free and esterified cholesterol, triglycerides, phospholipids (except for lysophosphatidylcholine) and sphingomyelin in comparison to native LDL. On the other hand, levels of mono-, and diglycerides, lysophosphatidylcholine and free fatty acids were higher in cmLDL than in native LDL. Our study demonstrated that lipid composition of cmLDL from atherosclerotic patients was altered in comparison to healthy subjects. In particular, phospholipid content was decreased, and free fatty acids levels were increased in cmLDL. This strengthens the hypothesis of multiple modification of LDL particles in the bloodstream and underscores the clinical importance of desialylated LDL as a possible marker of atherosclerosis progression. PMID:27558696

  8. High-density lipoprotein, mitochondrial dysfunction and cell survival mechanisms.

    Science.gov (United States)

    White, C Roger; Giordano, Samantha; Anantharamaiah, G M

    2016-09-01

    Ischemic injury is associated with acute myocardial infarction, percutaneous coronary intervention, coronary artery bypass grafting and open heart surgery. The timely re-establishment of blood flow is critical in order to minimize cardiac complications. Reperfusion after a prolonged ischemic period, however, can induce severe cardiomyocyte dysfunction with mitochondria serving as a major target of ischemia/reperfusion (I/R) injury. An increase in the formation of reactive oxygen species (ROS) induces damage to mitochondrial respiratory complexes leading to uncoupling of oxidative phosphorylation. Mitochondrial membrane perturbations also contribute to calcium overload, opening of the mitochondrial permeability transition pore (mPTP) and the release of apoptotic mediators into the cytoplasm. Clinical and experimental studies show that ischemic preconditioning (ICPRE) and postconditioning (ICPOST) attenuate mitochondrial injury and improve cardiac function in the context of I/R injury. This is achieved by the activation of two principal cell survival cascades: 1) the Reperfusion Injury Salvage Kinase (RISK) pathway; and 2) the Survivor Activating Factor Enhancement (SAFE) pathway. Recent data suggest that high density lipoprotein (HDL) mimics the effects of conditioning protocols and attenuates myocardial I/R injury via activation of the RISK and SAFE signaling cascades. In this review, we discuss the roles of apolipoproteinA-I (apoA-I), the major protein constituent of HDL, and sphingosine 1-phosphate (S1P), a lysosphingolipid associated with small, dense HDL particles as mediators of cardiomyocyte survival. Both apoA-I and S1P exert an infarct-sparing effect by preventing ROS-dependent injury and inhibiting the opening of the mPTP. PMID:27150975

  9. Large-scale preparation of the homogeneous LolA–lipoprotein complex and efficient in vitro transfer of lipoproteins to the outer membrane in a LolB-dependent manner

    OpenAIRE

    Watanabe, Shoji; Oguchi, Yuki; Yokota, Naoko; Tokuda, Hajime

    2007-01-01

    An ATP-binding cassette transporter LolCDE complex of Escherichia coli releases lipoproteins destined to the outer membrane from the inner membrane as a complex with a periplasmic chaperone, LolA. Interaction of the LolA–lipoprotein complex with an outer membrane receptor, LolB, then causes localization of lipoproteins to the outer membrane. As far as examined, formation of the LolA–lipoprotein complex strictly depends on ATP hydrolysis by the LolCDE complex in the presence of LolA. It has be...

  10. Phanerochaete mutants with enhanced ligninolytic activity

    International Nuclear Information System (INIS)

    In addition to lignin, the white rot fungus Phanerochaete chrysosporium has the ability to degrade a wide spectrum of recalcitrant organo pollutants in soils and aqueous media. Most of the organic compounds are degraded under ligninolytic conditions with the involvement of the extracellular enzymes, lignin peroxidases, and manganese-dependent peroxidases, which are produced as secondary metabolites triggered by conditions of nutrient starvation (e.g., nitrogen limitation). The fungus and its enzymes can thus provide alternative technologies for bioremediation, bio pulping, bio bleaching, and other industrial applications. The efficiency and effectiveness of the fungus can be enhanced by increasing production and secretion of the important enzymes in large quantities and as primary metabolites under enriched conditions. One way this can be achieved is through isolation of mutants that are deregulated, or are hyper producers or super secretors of key enzymes under enriched conditions. Through UV-light and γ-ray mutagenesis, we have isolated a variety of mutants, some of which produce key enzymes of the ligninolytic system under high-nitrogen growth conditions. One of the mutants, 76UV, produced 272 U of lignin peroxidases enzyme activity/L after 9 d under high nitrogen (although the parent strain does not produce this enzyme under these conditions). The mutant and the parent strains produced up to 54 and 62 U/L, respectively, of the enzyme activity under low nitrogen growth conditions during this period. In some experiments, the mutant showed 281 U/L of enzyme activity under high nitrogen after 17 d

  11. Evaluation of high yielding mungbean mutants

    International Nuclear Information System (INIS)

    Mungbean is the second major (Vigna radiata (L.) Wilczek) pulse crop in Pakistan, after chickpea, and is the main pulse crop grown during the spring season in the province of Sindh. Its yield is very low (450 kg/ha) which is mainly due to the non-availability of pure seed of high yield potential genotypes. Keeping in view the importance of induced mutations in all field crops and particularly in the evolution of mungbean cultivars, an induced mutation programme was initiated at AEARC, Tandojam during 1985. Since then a large number of mutants have been developed and are at various stages of evaluation. Among them two mungbean mutants (AEM 6/20 and AEM 32/20) isolated from the treated population of a local cultivar '6601' with 200 Gy gamma-ray treatment gave very encouraging performance in station as well as zonal trials. On the basis of these results they were promoted in the National Trials, where they remained under evaluation for four years during spring as well as summer seasons. The pool data of four consecutive years of both seasons indicated that mutant lines AEM 32/20 and AEM 6/20 produced 1298 and 1246 kg/ha grain yield respectively as compared to the check variety 'NM 121-25' (1055 kg/ha) evolved at NIAB, Faisalabad through induced mutations. The seed yield increase over the check variety ranged from 18-23%. These two mungbean mutants have short stature combined with short duration and synchrony in maturity. Keeping in view the outstanding performance of these mutant lines, variety release proposals are being submitted to the Technical Sub-Committee for approval of varieties and techniques

  12. 10 October 2013 - D. Braun First Deputy Minister for Regional Development, Czech Republic, P. Styczeń Deputy Minister of Transport, Construction and Maritime Economy, Republic of Poland and F. Palko State Secretary, Ministry of Transport, Construction and Regional Development, Slovak Republic visiting the LHC tunnel at Point 1 with Technology Department, Vacuum, Surfaces and Coatings Group Leader J. M. Jimenez and signing the Guest book with CERN Director-General R. Heuer

    CERN Multimedia

    Anna Pantelia

    2013-01-01

    10 October 2013 - D. Braun First Deputy Minister for Regional Development, Czech Republic, P. Styczeń Deputy Minister of Transport, Construction and Maritime Economy, Republic of Poland and F. Palko State Secretary, Ministry of Transport, Construction and Regional Development, Slovak Republic visiting the LHC tunnel at Point 1 with Technology Department, Vacuum, Surfaces and Coatings Group Leader J. M. Jimenez and signing the Guest book with CERN Director-General R. Heuer

  13. Metabolism of a Lipid Nanoemulsion Resembling Low-Density Lipoprotein in Patients with Grade III Obesity

    Science.gov (United States)

    Dantas, Simone Alves; Ficker, Elisabeth Salvatori; Vinagre, Carmen G. C.; Ianni, Barbara Maria; Maranhão, Raul Cavalcante; Mady, Charles

    2010-01-01

    INTRODUCTION: Obesity increases triglyceride levels and decreases high-density lipoprotein concentrations in plasma. Artificial emulsions resembling lipidic plasma lipoprotein structures have been used to evaluate low-density lipoprotein metabolism. In grade III obesity, low density lipoprotein metabolism is poorly understood. OBJECTIVE: To evaluate the kinetics with which a cholesterol-rich emulsion (called a low-density emulsion) binds to low-density lipoprotein receptors in a group of patients with grade III obesity by the fractional clearance rate. METHODS: A low-density emulsion was labeled with [14C]-cholesterol ester and [3H]-triglycerides and injected intravenously into ten normolipidemic non-diabetic patients with grade III obesity [body mass index higher than 40 kg/m2] and into ten non-obese healthy controls. Blood samples were collected over 24 hours to determine the plasma decay curve and to calculate the fractional clearance rate. RESULTS: There was no difference regarding plasma levels of total cholesterol or low-density lipoprotein cholesterol between the two groups. The fractional clearance rate of triglycerides was 0.086 ± 0.044 in the obese group and 0.122 ± 0.026 in the controls (p = 0.040), and the fractional clearance rate of cholesterol ester (h−1) was 0.052 ± 0.021 in the obese subjects and 0.058 ± 0.015 (p = 0.971) in the controls. CONCLUSION: Grade III obese subjects exhibited normal low-density lipoprotein removal from plasma as tested by the nanoemulsion method, but triglyceride removal was slower. PMID:20126342

  14. Metabolism of a lipid nanoemulsion resembling low-density lipoprotein in patients with grade III obesity

    Directory of Open Access Journals (Sweden)

    Simone Alves Dantas

    2010-01-01

    Full Text Available INTRODUCTION: Obesity increases triglyceride levels and decreases high-density lipoprotein concentrations in plasma. Artificial emulsions resembling lipidic plasma lipoprotein structures have been used to evaluate low-density lipoprotein metabolism. In grade III obesity, low density lipoprotein metabolism is poorly understood. OBJECTIVE: To evaluate the kinetics with which a cholesterol-rich emulsion (called a low-density emulsion binds to low-density lipoprotein receptors in a group of patients with grade III obesity by the fractional clearance rate. METHODS: A low-density emulsion was labeled with [14C]-cholesterol ester and [³H]-triglycerides and injected intravenously into ten normolipidemic non-diabetic patients with grade III obesity [body mass index higher than 40 kg/m²] and into ten non-obese healthy controls. Blood samples were collected over 24 hours to determine the plasma decay curve and to calculate the fractional clearance rate. RESULTS: There was no difference regarding plasma levels of total cholesterol or low-density lipoprotein cholesterol between the two groups. The fractional clearance rate of triglycerides was 0.086 ± 0.044 in the obese group and 0.122 ± 0.026 in the controls (p = 0.040, and the fractional clearance rate of cholesterol ester (h-1 was 0.052 ± 0.021 in the obese subjects and 0.058 ± 0.015 (p = 0.971 in the controls. CONCLUSION: Grade III obese subjects exhibited normal low-density lipoprotein removal from plasma as tested by the nanoemulsion method, but triglyceride removal was slower.

  15. Characterization of Two Metal Binding Lipoproteins as Vaccine Candidates for Enterococcal Infections.

    Directory of Open Access Journals (Sweden)

    Felipe Romero-Saavedra

    Full Text Available Enterococcus faecium and faecalis are Gram-positive opportunistic pathogens that have become leading causes of nosocomial infections over the last decades. Especially multidrug resistant enterococci have become a challenging clinical problem worldwide. Therefore, new treatment options are needed and the identification of alternative targets for vaccine development has emerged as a feasible alternative to fight the infections caused by these pathogens.We extrapolate the transcriptomic data from a mice peritonitis infection model in E. faecalis to identify putative up-regulated surface proteins under infection conditions in E. faecium. After the bionformatic analyses two metal binding lipoproteins were identified to have a high homology (>72% between the two species, the manganese ABC transporter substrate-binding lipoprotein (PsaAfm, and the zinc ABC transporter substrate-binding lipoprotein (AdcAfm. These candidate lipoproteins were overexpressed in Escherichia coli and purified. The recombinant proteins were used to produce rabbit polyclonal antibodies that were able to induce specific opsonic antibodies that mediated killing of the homologous strain E. faecium E155 as well as clinical strains E. faecium E1162, Enterococcus faecalis 12030, type 2 and type 5. Mice were passively immunized with the antibodies raised against recombinant lipoproteins, showing significant reduction of colony counts in mice livers after the bacterial challenge and demonstrating the efficacy of these metal binding lipoproteins as promising vaccine candidates to treat infections caused by these enterococcal pathogens.Overall, our results demonstrate that these two metal binding lipoproteins elicited specific, opsonic and protective antibodies, with an extensive cross-reactivity and serotype-independent coverage among these two important nocosomial pathogens. Pointing these two protein antigens as promising immunogens, that can be used as single components or as carrier

  16. Triglyceride-Rich Lipoproteins and Atherosclerotic Cardiovascular Disease: New Insights From Epidemiology, Genetics, and Biology.

    Science.gov (United States)

    Nordestgaard, Børge G

    2016-02-19

    Scientific interest in triglyceride-rich lipoproteins has fluctuated over the past many years, ranging from beliefs that these lipoproteins cause atherosclerotic cardiovascular disease (ASCVD) to being innocent bystanders. Correspondingly, clinical recommendations have fluctuated from a need to reduce levels to no advice on treatment. New insight in epidemiology now suggests that these lipoproteins, marked by high triglycerides, are strong and independent predictors of ASCVD and all-cause mortality, and that their cholesterol content or remnant cholesterol likewise are strong predictors of ASCVD. Of all adults, 27% have triglycerides >2 mmol/L (176 mg/dL), and 21% have remnant cholesterol >1 mmol/L (39 mg/dL). For individuals in the general population with nonfasting triglycerides of 6.6 mmol/L (580 mg/dL) compared with individuals with levels of 0.8 mmol/L (70 mg/dL), the risks were 5.1-fold for myocardial infarction, 3.2-fold for ischemic heart disease, 3.2-fold for ischemic stroke, and 2.2-fold for all-cause mortality. Also, genetic studies using the Mendelian randomization design, an approach that minimizes problems with confounding and reverse causation, now demonstrate that triglyceride-rich lipoproteins are causally associated with ASCVD and all-cause mortality. Finally, genetic evidence also demonstrates that high concentrations of triglyceride-rich lipoproteins are causally associated with low-grade inflammation. This suggests that an important part of inflammation in atherosclerosis and ASCVD is because of triglyceride-rich lipoprotein degradation and uptake into macrophage foam cells in the arterial intima. Taken together, new insights now strongly suggest that elevated triglyceride-rich lipoproteins represent causal risk factors for low-grade inflammation, ASCVD, and all-cause mortality. PMID:26892957

  17. Genetic Risk Scores Associated with Baseline Lipoprotein Subfraction Concentrations Do Not Associate with Their Responses to Fenofibrate

    Directory of Open Access Journals (Sweden)

    Alexis C. Frazier-Wood

    2014-08-01

    Full Text Available Lipoprotein subclass concentrations are modifiable markers of cardiovascular disease risk. Fenofibrate is known to show beneficial effects on lipoprotein subclasses, but little is known about the role of genetics in mediating the responses of lipoprotein subclasses to fenofibrate. A recent genomewide association study (GWAS associated several single nucleotide polymorphisms (SNPs with lipoprotein measures, and validated these associations in two independent populations. We used this information to construct genetic risk scores (GRSs for fasting lipoprotein measures at baseline (pre-fenofibrate, and aimed to examine whether these GRSs also associated with the responses of lipoproteins to fenofibrate. Fourteen lipoprotein subclass measures were assayed in 817 men and women before and after a three week fenofibrate trial. We set significance at a Bonferroni corrected alpha <0.05 (p < 0.004. Twelve subclass measures changed with fenofibrate administration (each p = 0.003 to <0.0001. Mixed linear models which controlled for age, sex, body mass index (BMI, smoking status, pedigree and study-center, revealed that GRSs were associated with eight baseline lipoprotein measures (p < 0.004, however no GRS was associated with fenofibrate response. These results suggest that the mechanisms for changes in lipoprotein subclass concentrations with fenofibrate treatment are not mediated by the genetic risk for fasting levels.

  18. Genetic study of necrotic leaf pea (Pisum sativum L.) mutants

    International Nuclear Information System (INIS)

    Four pea (Pisum sativum L.) mutants characterized by necrotic leaves were isolated following mutagenesis. The mutants were shown to have single-gene recessive inheritance, characterized morphologically and for seed production. New mutants 1/704, 1/711M, XV/915 and 2/352 had similar phenotypes, respectively, to previously named mutants dgl (degenerating leaves), nec (necrosis), bls (brown leaf spots) and bls (brown leaf), but no allelism tests were made between the new and the previously reported mutants. Mutants 1/704 and 1/711M were shown to be non-allelic. The mutation in line 2/352 may be useful as a genetic marker

  19. Circulating lipoproteins are a crucial component of host defense against invasive Salmonella typhimurium infection.

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    Mihai G Netea

    Full Text Available BACKGROUND: Circulating lipoproteins improve the outcome of severe Gram-negative infections through neutralizing lipopolysaccharides (LPS, thus inhibiting the release of proinflammatory cytokines. METHODS/PRINCIPAL FINDINGS: Low density lipoprotein receptor deficient (LDLR-/- mice, with a 7-fold increase in LDL, are resistant against infection with Salmonella typhimurium (survival 100% vs 5%, p<0.001, and 100 to 1000-fold lower bacterial burden in the organs, compared with LDLR+/+ mice. Protection was not due to differences in cytokine production, phagocytosis, and killing of Salmonella organisms. The differences were caused by the excess of lipoproteins, as hyperlipoproteinemic ApoE-/- mice were also highly resistant to Salmonella infection. Lipoproteins protect against infection by interfering with the binding of Salmonella to host cells, and preventing organ invasion. This leads to an altered biodistribution of the microorganisms during the first hours of infection: after intravenous injection of Salmonella into LDLR+/+ mice, the bacteria invaded the liver and spleen within 30 minutes of infection. In contrast, in LDLR-/- mice, Salmonella remained constrained to the circulation from where they were efficiently cleared, with decreased organ invasion. CONCLUSIONS: plasma lipoproteins are a potent host defense mechanism against invasive Salmonella infection, by blocking adhesion of Salmonella to the host cells and subsequent tissue invasion.

  20. Vegetable oils affect the composition of lipoproteins in sea bream (Sparus aurata).

    Science.gov (United States)

    Caballero, Maria José; Torstensen, Bente E; Robaina, Lidia; Montero, Daniel; Izquierdo, Marisol

    2006-11-01

    The aim of the present study was to determine the influence of the dietary fatty acid profile on the lipoprotein composition in sea bream fed different vegetable oils. Six experimental diets were formulated combining fish oil with three vegetable oils (soybean, rapeseed, linseed) in order to obtain 60-80 % (w/w) fish-oil replacement. VLDL, LDL and HDL in plasma samples were obtained by sequential centrifugal flotation. The lipid class, protein content and fatty acid composition of each lipoprotein fraction were analysed. HDL was the predominant lipoprotein in sea bream plasma containing the highest proportion of protein (34 %) and phosphatidylcholine. LDL presented a high content of cholesterol, whereas triacylglycerol comprised a larger proportion of VLDL. The lipid class of the lipoprotein fractions was affected by the dietary vegetable oils. Thus, a high dietary inclusion of soyabean and linseed oil (80 %) increased the cholesterol in HDL and LDL in comparison to fish oil. Similarly, the triacylglycerol concentration of VLDL was increased in fish fed 80 % soyabean and linseed oils owing to the low n-3 highly unsaturated fatty acid content of these diets. Lipoprotein fatty acid composition easily responded to dietary fatty acid composition. VLDL was the fraction more affected by dietary fatty acid, followed by LDL and HDL. The n-3 highly unsaturated fatty acid content increased in the order VLDL less than LDL and less than HDL, regardless of dietary vegetable oils.

  1. Relationship between Serum Lipoprotein Ratios and Insulin Resistance in Polycystic Ovary Syndrome

    Directory of Open Access Journals (Sweden)

    Shou-Kui Xiang

    2012-01-01

    Full Text Available Objective. To investigate the association between serum lipoprotein ratios and insulin resistance in women with polycystic ovarian syndrome (PCOS. Methods. 105 PCOS patients and 109 controls were randomly enrolled in the study. Serum levels of luteinizing hormone (LH, follicle-stimulating hormone (FSH, estradiol (E2, total testosterone (T, fasting glucose (FBG, fasting insulin (FINS, serum triglycerides (TG, total cholesterol (TC, high-density lipoprotein (HDL-C, and low-density lipoprotein (LDL-C levels were checked, and then TG/HDL-C ratio, TC/HDL-C, ratio and LDL-C/HDL-C ratio were calculated. The homeostasis model assessment of insulin resistance (HOMA-IR was used to calculate the insulin resistance. Results. All lipoprotein ratios were significantly higher in PCOS patients as compared to healthy controls (<0.05. TG/HDL-C ratio, TC/HDL-C ratio, and LDL-C/HDL-C ratio were significantly correlated with HOMA-IR (<0.05. The ROC curve demonstrated that TC/HDL-C ratio had higher sensitivity and specificity in diagnosing PCOS with insulin resistance. Conclusion. This study demonstrates that serum lipoprotein ratio significantly correlates with insulin resistance and can be used as the marker of insulin resistance in PCOS patients.

  2. Cultured human astrocytes secrete large cholesteryl ester- andtriglyceride-rich lipoproteins along with endothelial lipase

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lin; Liu, Yanzhu; Forte, Trudy M.; Chisholm, Jeffrey W.; Parks, John S.; Shachter, Neil S.

    2003-12-01

    We cultured normal human astrocytes and characterized their secreted lipoproteins. Human astrocytes secreted lipoproteins in the size range of plasma VLDL (Peak 1), LDL (Peak 2), HDL (Peak 3) and a smaller peak (Peak 4), as determined by gel filtration chromatography, nondenaturing gradient gel electrophoresis and transmission electron microscopy. Cholesterol enrichment of astrocytes led to a particular increase in Peak 1. Almost all Peak 2, 3 and 4 cholesterol and most Peak 1 cholesterol was esterified (unlike mouse astrocyte lipoproteins, which exhibited similar peaks but where cholesterol was predominantly non-esterified). Triglycerides were present at about 2/3 the level of cholesterol. LCAT was detected along with two of its activators, apolipoprotein (apo) A-IV and apoC-I. ApoA-I and apoA-II mRNA and protein were absent. ApoJ was present equally in all peaks but apoE was present predominantly in peaks 3 and 4. ApoB was not detected. The electron microscopic appearance of Peak 1 lipoproteins suggested partial lipolysis leading to the detection of a heparin-releasable triglyceride lipase consistent with endothelial lipase. The increased neuronal delivery of lipids from large lipoprotein particles, for which apoE4 has greater affinity than does apoE3, may be a mechanism whereby the apoE {var_epsilon}4 allele contributes to neurodegenerative risk.

  3. Role of heparanase on hepatic uptake of intestinal derived lipoprotein and fatty streak formation in mice.

    Directory of Open Access Journals (Sweden)

    David Planer

    Full Text Available BACKGROUND: Heparanase modulates the level of heparan sulfate proteoglycans (HSPGs which have an important role in multiple cellular processes. Recent studies indicate that HSPGs have an important function in hepatic lipoprotein handling and processes involving removal of lipoprotein particles. PRINCIPAL FINDINGS: To determine the effects of decreased HSPGs chain length on lipoprotein metabolism and atherosclerosis, transgenic mice over-expressing the human heparanase gene were studied. Hepatic lipid uptake in hpa-Tg mice were evaluated by giving transgenic mice oral fat loads and labeled retinol. Sections of aorta from mice over-expressing heparanase (hpa-Tg and controls (C57/BL6 fed an atherogenic diet were examined for evidence of atherosclerosis. Heparanase over-expression results in reduced hepatic clearance of postprandial lipoproteins and higher levels of fasting and postprandial serum triglycerides. Heparanase over-expression also induces formation of fatty streaks in the aorta. The mean lesion cross-sectional area in heparanase over-expressing mice was almost 6 times higher when compared to control mice (23,984 µm(2±5,922 vs. 4,189 µm(2±1,130, p<0.001. CONCLUSIONS: Over-expression of heparanase demonstrates the importance of HSPGs for the uptake of intestinal derived lipoproteins and its role in the formation of fatty streaks.

  4. PNRI mutant variety: sansevieria 'Sword of Ibe'

    International Nuclear Information System (INIS)

    Sansevieria 'Sword of Ibe,' registered by the Philippine Nuclear Research Institute as NSIC 2008 Or-66, is a chlorophyll mutant of Sansevieria trifasciata 'Moonshine' developed by treating its suckers or shoots arising from a rhizome with acute gamma radiation from a Cobalt-60 source. The new mutant is identical in growth habit and vigor to Sansevieria 'Moonshine,' also known as Moonglow. Results of this mutation breeding experiment showed that leaf color and flowering were altered by gamma irradiation without changing the other characteristics of the plant. Propagation is true-to-type by separation of sucker and top cutting. The plant is recommended for use as landscaping material and as pot plant for indoor and outdoor use. The leaves may be harvested as cut foliage for Japanese flower arrangements. (author)

  5. Reliability of Calculated Low-Density Lipoprotein Cholesterol.

    Science.gov (United States)

    Meeusen, Jeffrey W; Snozek, Christine L; Baumann, Nikola A; Jaffe, Allan S; Saenger, Amy K

    2015-08-15

    Aggressive low-density lipoprotein cholesterol (LDL-C)-lowering strategies are recommended for prevention of cardiovascular events in high-risk populations. Guidelines recommend a 30% to 50% reduction in at-risk patients even when LDL-C concentrations are between 70 and 130 mg/dl (1.8 to 3.4 mmol/L). However, calculation of LDL-C by the Friedewald equation is the primary laboratory method for routine LDL-C measurement. We compared the accuracy and reproducibility of calculated LDL-C <130 mg/dl (3.4 mmol/L) to LDL-C measured by β quantification (considered the gold standard method) in 15,917 patients with fasting triglyceride concentrations <400 mg/dl (4.5 mmol/L). Both variation and bias of calculated LDL-C increased at lower values of measured LDL-C. The 95% confidence intervals for a calculated LDL-C of 70 mg/dl (1.8 mmol/L) and 30 mg/dl (0.8 mmol/L) were 60 to 86 mg/dl (1.6 to 2.2 mmol/L) and 24 to 60 mg/dl (0.6 to 1.6 mmol/L), respectively. Previous recommendations have emphasized the requirement for a fasting sample with triglycerides <400 mg/dl (4.5 mmol/L) to calculate LDL-C by the Friedewald equation. However, no recommendations have addressed the appropriate lower reportable limit for calculated LDL-C. In conclusion, calculated LDL-C <30 mg/dl (0.8 mmol/L) should not be reported because of significant deviation from the gold standard measured LDL-C results, and caution is advised when using calculated LDL-CF values <70 mg/dl (1.8 mmol/L) to make treatment decisions.

  6. Human endothelial progenitor cells internalize high-density lipoprotein.

    Science.gov (United States)

    Srisen, Kaemisa; Röhrl, Clemens; Meisslitzer-Ruppitsch, Claudia; Ranftler, Carmen; Ellinger, Adolf; Pavelka, Margit; Neumüller, Josef

    2013-01-01

    Endothelial progenitor cells (EPCs) originate either directly from hematopoietic stem cells or from a subpopulation of monocytes. Controversial views about intracellular lipid traffic prompted us to analyze the uptake of human high density lipoprotein (HDL), and HDL-cholesterol in human monocytic EPCs. Fluorescence and electron microscopy were used to investigate distribution and intracellular trafficking of HDL and its associated cholesterol using fluorescent surrogates (bodipy-cholesterol and bodipy-cholesteryl oleate), cytochemical labels and fluorochromes including horseradish peroxidase and Alexa Fluor® 568. Uptake and intracellular transport of HDL were demonstrated after internalization periods from 0.5 to 4 hours. In case of HDL-Alexa Fluor® 568, bodipy-cholesterol and bodipy-cholesteryl oleate, a photooxidation method was carried out. HDL-specific reaction products were present in invaginations of the plasma membrane at each time of treatment within endocytic vesicles, in multivesicular bodies and at longer periods of uptake, also in lysosomes. Some HDL-positive endosomes were arranged in form of "strings of pearl"- like structures. HDL-positive multivesicular bodies exhibited intensive staining of limiting and vesicular membranes. Multivesicular bodies of HDL-Alexa Fluor® 568-treated EPCs showed multilamellar intra-vacuolar membranes. At all periods of treatment, labeled endocytic vesicles and organelles were apparent close to the cell surface and in perinuclear areas around the Golgi apparatus. No HDL-related particles could be demonstrated close to its cisterns. Electron tomographic reconstructions showed an accumulation of HDL-containing endosomes close to the trans-Golgi-network. HDL-derived bodipy-cholesterol was localized in endosomal vesicles, multivesicular bodies, lysosomes and in many of the stacked Golgi cisternae and the trans-Golgi-network Internalized HDL-derived bodipy-cholesteryl oleate was channeled into the lysosomal intraellular

  7. Genetic analysis of intracapillary glomerular lipoprotein deposits in aging mice.

    Directory of Open Access Journals (Sweden)

    Gerda A Noordmans

    Full Text Available BACKGROUND: Renal aging is characterized by functional and structural changes like decreased glomerular filtration rate, and glomerular, tubular and interstitial damage. To gain insight in pathways involved in renal aging, we studied aged mouse strains and used genetic analysis to identify genes associated with aging phenotypes. METHODS: Upon morphological screening in kidneys from 20-month-old mice from 26 inbred strains we noted intracapillary PAS-positive deposits. The severity of these deposits was quantified by scoring of a total of 50 glomeruli per section (grade 0-4. Electron microscopy and immunohistochemical staining for apoE, apoB, apoA-IV and perilipin-2 was performed to further characterize the lesions. To identify loci associated with these PAS-positive intracapillary glomerular deposits, we performed haplotype association mapping. RESULTS: Six out of 26 mouse strains showed glomerular PAS-positive deposits. The severity of these deposits varied: NOD(0.97, NZW(0.41, NON(0.30, B10(0.21, C3 H(0.9 and C57BR(0.7. The intracapillary deposits were strongly positive for apoE and weakly positive for apoB and apoA-IV. Haplotype association mapping showed a strong association with a 30-Kb haplotype block on Chr 1 within the Esrrg gene. We investigated 1 Mb on each site of this region, which includes the genes Spata17, Gpatch2, Esrrg, Ush2a and Kctd3. CONCLUSIONS: By analyzing 26 aged mouse strains we found that some strains developed an intracapillary PAS and apoE-positive lesion and identified a small haplotype block on Chr 1 within the Esrrg gene to be associated with these lipoprotein deposits. The region spanning this haplotype block contains the genes Spata17, Gpatch2, Esrrg, Ush2a and Kctd3, which are all highly expressed in the kidney. Esrrg might be involved in the evolvement of these glomerular deposits by influencing lipid metabolism and possibly immune reponses.

  8. Lipoprotein X Causes Renal Disease in LCAT Deficiency.

    Directory of Open Access Journals (Sweden)

    Alice Ossoli

    Full Text Available Human familial lecithin:cholesterol acyltransferase (LCAT deficiency (FLD is characterized by low HDL, accumulation of an abnormal cholesterol-rich multilamellar particle called lipoprotein-X (LpX in plasma, and renal disease. The aim of our study was to determine if LpX is nephrotoxic and to gain insight into the pathogenesis of FLD renal disease. We administered a synthetic LpX, nearly identical to endogenous LpX in its physical, chemical and biologic characteristics, to wild-type and Lcat-/- mice. Our in vitro and in vivo studies demonstrated an apoA-I and LCAT-dependent pathway for LpX conversion to HDL-like particles, which likely mediates normal plasma clearance of LpX. Plasma clearance of exogenous LpX was markedly delayed in Lcat-/- mice, which have low HDL, but only minimal amounts of endogenous LpX and do not spontaneously develop renal disease. Chronically administered exogenous LpX deposited in all renal glomerular cellular and matrical compartments of Lcat-/- mice, and induced proteinuria and nephrotoxic gene changes, as well as all of the hallmarks of FLD renal disease as assessed by histological, TEM, and SEM analyses. Extensive in vivo EM studies revealed LpX uptake by macropinocytosis into mouse glomerular endothelial cells, podocytes, and mesangial cells and delivery to lysosomes where it was degraded. Endocytosed LpX appeared to be degraded by both human podocyte and mesangial cell lysosomal PLA2 and induced podocyte secretion of pro-inflammatory IL-6 in vitro and renal Cxl10 expression in Lcat-/- mice. In conclusion, LpX is a nephrotoxic particle that in the absence of Lcat induces all of the histological and functional hallmarks of FLD and hence may serve as a biomarker for monitoring recombinant LCAT therapy. In addition, our studies suggest that LpX-induced loss of endothelial barrier function and release of cytokines by renal glomerular cells likely plays a role in the initiation and progression of FLD nephrosis.

  9. Human endothelial progenitor cells internalize high-density lipoprotein.

    Directory of Open Access Journals (Sweden)

    Kaemisa Srisen

    Full Text Available Endothelial progenitor cells (EPCs originate either directly from hematopoietic stem cells or from a subpopulation of monocytes. Controversial views about intracellular lipid traffic prompted us to analyze the uptake of human high density lipoprotein (HDL, and HDL-cholesterol in human monocytic EPCs. Fluorescence and electron microscopy were used to investigate distribution and intracellular trafficking of HDL and its associated cholesterol using fluorescent surrogates (bodipy-cholesterol and bodipy-cholesteryl oleate, cytochemical labels and fluorochromes including horseradish peroxidase and Alexa Fluor® 568. Uptake and intracellular transport of HDL were demonstrated after internalization periods from 0.5 to 4 hours. In case of HDL-Alexa Fluor® 568, bodipy-cholesterol and bodipy-cholesteryl oleate, a photooxidation method was carried out. HDL-specific reaction products were present in invaginations of the plasma membrane at each time of treatment within endocytic vesicles, in multivesicular bodies and at longer periods of uptake, also in lysosomes. Some HDL-positive endosomes were arranged in form of "strings of pearl"- like structures. HDL-positive multivesicular bodies exhibited intensive staining of limiting and vesicular membranes. Multivesicular bodies of HDL-Alexa Fluor® 568-treated EPCs showed multilamellar intra-vacuolar membranes. At all periods of treatment, labeled endocytic vesicles and organelles were apparent close to the cell surface and in perinuclear areas around the Golgi apparatus. No HDL-related particles could be demonstrated close to its cisterns. Electron tomographic reconstructions showed an accumulation of HDL-containing endosomes close to the trans-Golgi-network. HDL-derived bodipy-cholesterol was localized in endosomal vesicles, multivesicular bodies, lysosomes and in many of the stacked Golgi cisternae and the trans-Golgi-network Internalized HDL-derived bodipy-cholesteryl oleate was channeled into the lysosomal

  10. Genetic Analysis of Dictyostelium Slug Phototaxis Mutants

    OpenAIRE

    Darcy, P. K.; Wilczynska, Z.; Fisher, P R

    1994-01-01

    Mapping and complementation analysis with 17 phototaxis mutations has established 11 complementation groups phoA-phoK distributed over six linkage groups. Statistical calculations from the complementation data yielded 17 as the maximum likelihood estimate of the number of pho genes assuming all loci are equally mutable. Most of the phototaxis mutants were found to exhibit bimodal phototaxis and all were found to be impaired in positive thermotaxis supporting convergence of the photosensory an...

  11. Characterization of a Legionella micdadei mip mutant

    DEFF Research Database (Denmark)

    O'Connell, W A; Bangsborg, Jette Marie; Cianciotto, N P

    1995-01-01

    The pathogenesis of Legionella micdadei is dependent upon its ability to infect alveolar phagocytes. To better understand the basis of intracellular infection by this organism, we examined the importance of its Mip surface protein. In Legionella pneumophila, Mip promotes infection of both human m...... into the phagocyte. Similarly, the mutant was less able to parasitize Hartmannella amoebae. Taken together, these data argue that Mip specifically potentiates intracellular growth by L. micdadei....

  12. Selection of Bacillus subtilis mutants impaired in ammonia assimilation.

    OpenAIRE

    Dean, D R; Aronson, A I

    1980-01-01

    The selection of Bacillus subtilis mutants capable of using D-histidine to fulfill a requirement for L-histidine resulted in mutants with either no glutamate synthase activity or increased amounts of an altered glutamine synthetase.

  13. Grain product of 34 soya mutant lines

    International Nuclear Information System (INIS)

    This work was development with the objective of obtaining information of the agronomic behavior of 34 soya mutant lines (R4M18) for human consumption and this way to select the 2 better lines. The genetic materials were obtained starting from the variety ISAAEG-B M2 by means of the application of recurrent radiation with Co60 gammas, to a dose of 350 Gray for the first two generations and both later to 200 Gray and selection during 17 cycles, being obtained the 34 better lines mutants with agronomic characteristic wanted and good flavor. The obtained results were that the mutant lines L25 and L32 produced the major quantity in branches/plant number with 7.5 and 7.25, pods/plant number with 171.25 and 167, grains/plant number with 350.89 and 333.07 and grain product (ton/ha) to 15% of humidity 5.15 and 4.68 ton/ha, respectively. (Author)

  14. Apolipoprotein(a) phenotypes and lipoprotein(a) concentrations in patients with hyperthyroidism

    DEFF Research Database (Denmark)

    Klausen, I C; Hegedüs, L; Hansen, P S;

    1995-01-01

    are inversely correlated. High plasma levels of Lp(a) are associated with atherosclerotic diseases. It is therefore of interest to study whether factors other than the apo(a) gene locus are involved in the regulation of Lp(a) concentrations. We measured plasma concentrations of Lp(a) and other lipoproteins.......01) and in patients with low molecular weight apo(a) phenotypes (n = 16; P levels LDL cholesterol and apoB in untreated hyperthyroidism may result from increased LDL receptor activity. The increase in Lp(a) levels were not correlated......Lipoprotein(a) [Lp(a)] is a low-density lipoprotein (LDL) particle in which apolipoprotein B-100 (apoB) is attached to a glycoprotein called apolipoprotein(a) [apo(a)]. Apo(a) has several genetically determined phenotypes differing in molecular weight, to which Lp(a) concentrations in plasma...

  15. Lipoprotein predictors of cardiovascular events in statin-treated patients with coronary heart disease

    DEFF Research Database (Denmark)

    Holme, Ingar; Cater, Nilo B; Faergeman, Ole;

    2008-01-01

    the relationships between on-treatment levels of lipoprotein components to subsequent major coronary events (MCE). FINDINGS: Variables related to low-density lipoprotein cholesterol (LDL-C) carried more predictive information than those related to high-density lipoprotein cholesterol (HDL-C), but LDL-C was less...... predictive than both non-HDL-C and apoB. The ratio of apoB to apoA-1 was most strongly related to MCE. However, for estimating differences in relative risk reduction between the treatment groups, apoB and non-HDL-C were the strongest predictors. INTERPRETATION: The on-treatment level of apoB/apoA-1...

  16. Determining the risk of cardiovascular disease using ion mobility of lipoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Benner, W. Henry; Krauss, Ronald M.; Blanche, Patricia J.

    2010-05-11

    A medical diagnostic method and instrumentation system for analyzing noncovalently bonded agglomerated biological particles is described. The method and system comprises: a method of preparation for the biological particles; an electrospray generator; an alpha particle radiation source; a differential mobility analyzer; a particle counter; and data acquisition and analysis means. The medical device is useful for the assessment of human diseases, such as cardiac disease risk and hyperlipidemia, by rapid quantitative analysis of lipoprotein fraction densities. Initially, purification procedures are described to reduce an initial blood sample to an analytical input to the instrument. The measured sizes from the analytical sample are correlated with densities, resulting in a spectrum of lipoprotein densities. The lipoprotein density distribution can then be used to characterize cardiac and other lipid-related health risks.

  17. Method of assessing a lipid-related health risk based on ion mobility analysis of lipoproteins

    Energy Technology Data Exchange (ETDEWEB)

    Benner, W. Henry (Danville, CA); Krauss, Ronald M. (Berkeley, CA); Blanche, Patricia J. (Berkeley, CA)

    2010-12-14

    A medical diagnostic method and instrumentation system for analyzing noncovalently bonded agglomerated biological particles is described. The method and system comprises: a method of preparation for the biological particles; an electrospray generator; an alpha particle radiation source; a differential mobility analyzer; a particle counter; and data acquisition and analysis means. The medical device is useful for the assessment of human diseases, such as cardiac disease risk and hyperlipidemia, by rapid quantitative analysis of lipoprotein fraction densities. Initially, purification procedures are described to reduce an initial blood sample to an analytical input to the instrument. The measured sizes from the analytical sample are correlated with densities, resulting in a spectrum of lipoprotein densities. The lipoprotein density distribution can then be used to characterize cardiac and other lipid-related health risks.

  18. Lipophilic antioxidants and polyunsaturated fatty acids in lipoprotein classes: distribution and interaction

    DEFF Research Database (Denmark)

    Sunesen, V.H.; Weber, Christine; Hølmer, Gunhild Kofoed

    2001-01-01

    Objective: To study the lipoprotein distribution of supplemented coenzyme Q(10) (CoQ(10)), vitamin E, and polyunsaturated fatty acids (PUFA). Design: Balanced three- period crossover study. Setting: University research unit. Subjects: Eighteen apparently healthy free-living non-smoking volunteers...... the first period and then after each period. Plasma and isolated lipoproteins were analysed for cholesterol, triacylglycerol, alpha- and gamma -tocopherol, CoQ(10), and fatty acid composition. Results: Significant (P ... supplementations, but fish oil increased the amount of n-3 fatty acids at the expense of n-6 fatty acids. Conclusion: Lipoprotein distribution of CoQ(10) is markedly different from that of alpha -tocopherol, suggesting that they may be metabolised by distinct routes. alpha -Tocopherol is distributed similarly to n...

  19. Progress of cardioprotective effects of high density lipoprotein: function and mechanism

    Directory of Open Access Journals (Sweden)

    Hai-ge SUN

    2015-01-01

    Full Text Available The high density lipoprotein (HDL in human plasma is a heterogeneous lipoprotein consisting of roughly equal contents of lipid and protein in roughly equal content, and it consists of several subtypes. HDL possesses several well-documented functions, including anti-atherosclerosis by promoting reverse cholesterol transport, inhibiting the oxidative modification of low density lipoproteins (LDLs, inhibiting vascular inflammation, preventing thrombosis and apoptosis, and promoting endothelial repair. Recently, more cardiovascular protective functions of HDL have been found, mainly including the ability of suppressing immune inflammatory reaction, inhibiting the proliferation of hematopoietic stem cells, and regulating the plasma glucose level. It is of great importance to understand how different HDL subtypes contribute to the potentially cardioprotective functions. DOI: 10.11855/j.issn.0577-7402.2014.11.13

  20. Triglycerides and high-density lipoprotein cholesterol are associated with insulinemia in adolescents

    Directory of Open Access Journals (Sweden)

    Ramírez-López Guadalupe

    2006-01-01

    Full Text Available OBJECTIVE: The aim of this study was to evaluate the association between lipids and insulin concentration in adolescents. MATERIAL AND METHODS: A cross-sectional study of 350 adolescents aged 14-19 years old from a public high school in Guadalajara, in the state of Jalisco, Mexico, was conducted. Fasting insulin concentration was determined using microparticle enzyme immunoassay; total cholesterol and triglycerides were detected by standard enzymatic procedures; and low- and high-density lipoproteins were found using standard precipitation methods. Statistical analysis included linear multivariate regression. RESULTS: Serum triglycerides were associated positively with insulin fasting (beta= 0.003, p= 0.0001 and high-density lipoprotein cholesterol was negatively associated with insulin fasting in male adolescents 18-19 years old (beta= -0.03, p= 0.012. CONCLUSIONS: The relationships between triglycerides and insulin and between high-density lipoprotein cholesterol and insulin are already present in adolescence.

  1. Molecular characterization of phycobilisome regulatory mutants of Fremyella diplosiphon.

    OpenAIRE

    Bruns, B U; Briggs, W R; Grossman, A R

    1989-01-01

    Three classes of pigment mutants were generated in Fremyella diplosiphon in the course of electroporation experiments. The red mutant class had high levels of phycoerythrin in both red and green light and no inducible phycocyanin in red light. Thus, this mutant behaved as if it were always in green light, regardless of light conditions. Blue mutants exhibited normal phycoerythrin photoregulation, whereas the inducible phycocyanin was present at high levels in both red- and green-light-grown c...

  2. A Mutant of Mycobacterium smegmatis Defective in Dipeptide Transport

    OpenAIRE

    Bhatt, Achal; Green, Renee; Coles, Roswell; Condon, Michael; Connell, Nancy D.

    1998-01-01

    A mutant of Mycobacterium smegmatis unable to use the dipeptide carnosine (β-alanyl-l-histidine) as a sole carbon or nitrogen source was isolated. Carnosinase activity and the ability to grow on β-Ala and/or l-His were similar in the mutant and the wild type. However, the mutant showed significant impairment in the uptake of carnosine. This study is the first description of a peptide utilization mutant of a mycobacterium.

  3. Induced Dwarf Mutant in Catharanthus roseus with Enhanced Antibacterial Activity

    OpenAIRE

    Verma, A.K.; Singh, R R

    2010-01-01

    Evaluation of an ethyl methane sulphonate-induced dwarf mutant of Catharanthus roseus (L.) G. Don revealed that the mutant exhibited marked variation in morphometric parameters. The in vitro antibacterial activity of the aqueous and alcoholic leaf extracts of the mutant and control plants was investigated against medically important bacteria. The mutant leaf extracts showed enhanced antibacterial activity against all the tested bacteria except Bacillus subtilis.

  4. Induced dwarf mutant in Catharanthus roseus with enhanced antibacterial activity

    Directory of Open Access Journals (Sweden)

    Verma A

    2010-01-01

    Full Text Available Evaluation of an ethyl methane sulphonate-induced dwarf mutant of Catharanthus roseus (L. G. Don revealed that the mutant exhibited marked variation in morphometric parameters. The in vitro antibacterial activity of the aqueous and alcoholic leaf extracts of the mutant and control plants was investigated against medically important bacteria. The mutant leaf extracts showed enhanced antibacterial activity against all the tested bacteria except Bacillus subtilis.

  5. Induced Dwarf Mutant in Catharanthus roseus with Enhanced Antibacterial Activity

    Science.gov (United States)

    Verma, A. K.; Singh, R. R.

    2010-01-01

    Evaluation of an ethyl methane sulphonate-induced dwarf mutant of Catharanthus roseus (L.) G. Don revealed that the mutant exhibited marked variation in morphometric parameters. The in vitro antibacterial activity of the aqueous and alcoholic leaf extracts of the mutant and control plants was investigated against medically important bacteria. The mutant leaf extracts showed enhanced antibacterial activity against all the tested bacteria except Bacillus subtilis. PMID:21695004

  6. Insights on the structure and stability of Licanantase: a trimeric acid-stable coiled-coil lipoprotein from Acidithiobacillus thiooxidans

    Directory of Open Access Journals (Sweden)

    Fernando Abarca

    2014-08-01

    Full Text Available Licanantase (Lic is the major component of the secretome of Acidithiobacillus thiooxidans when grown in elemental sulphur. When used as an additive, Lic improves copper recovery from bioleaching processes. However, this recovery enhancement is not fully understood. In this context, our aim is to predict the 3D structure of Lic, to shed light on its structure-function relationships. Bioinformatics analyses on the amino acid sequence of Lic showed a great similarity with Lpp, an Escherichia coli Lipoprotein that can form stable trimers in solution. Lic and Lpp share the secretion motif, intracellular processing and alpha helix structure, as well as the distribution of hydrophobic residues in heptads forming a hydrophobic core, typical of coiled-coil structures. Cross-linking experiments showed the presence of Lic trimers, supporting our predictions. Taking the in vitro and in silico evidence as a whole, we propose that the most probable structure for Lic is a trimeric coiled-coil. According to this prediction, a suitable model for Lic was produced using the de novo algorithm “Rosetta Fold-and-Dock”. To assess the structural stability of our model, Molecular Dynamics (MD and Replica Exchange MD simulations were performed using the structure of Lpp and a 14-alanine Lpp mutant as controls, at both acidic and neutral pH. Our results suggest that Lic was the most stable structure among the studied proteins in both pH conditions. This increased stability can be explained by a higher number of both intermonomer hydrophobic contacts and hydrogen bonds, key elements for the stability of Lic’s secondary and tertiary structure.

  7. Insights on the structure and stability of Licanantase: a trimeric acid-stable coiled-coil lipoprotein from Acidithiobacillus thiooxidans.

    Science.gov (United States)

    Abarca, Fernando; Gutierrez-Maldonado, Sebastian E; Parada, Pilar; Martinez, Patricio; Maass, Alejandro; Perez-Acle, Tomas

    2014-01-01

    Licanantase (Lic) is the major component of the secretome of Acidithiobacillus thiooxidans when grown in elemental sulphur. When used as an additive, Lic improves copper recovery from bioleaching processes. However, this recovery enhancement is not fully understood. In this context, our aim is to predict the 3D structure of Lic, to shed light on its structure-function relationships. Bioinformatics analyses on the amino acid sequence of Lic showed a great similarity with Lpp, an Escherichia coli Lipoprotein that can form stable trimers in solution. Lic and Lpp share the secretion motif, intracellular processing and alpha helix structure, as well as the distribution of hydrophobic residues in heptads forming a hydrophobic core, typical of coiled-coil structures. Cross-linking experiments showed the presence of Lic trimers, supporting our predictions. Taking the in vitro and in silico evidence as a whole, we propose that the most probable structure for Lic is a trimeric coiled-coil. According to this prediction, a suitable model for Lic was produced using the de novo algorithm "Rosetta Fold-and-Dock". To assess the structural stability of our model, Molecular Dynamics (MD) and Replica Exchange MD simulations were performed using the structure of Lpp and a 14-alanine Lpp mutant as controls, at both acidic and neutral pH. Our results suggest that Lic was the most stable structure among the studied proteins in both pH conditions. This increased stability can be explained by a higher number of both intermonomer hydrophobic contacts and hydrogen bonds, key elements for the stability of Lic's secondary and tertiary structure.

  8. Radiation studies in Cajanus cajan: meiotic behaviour in some M/sub 2/ mutants

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, S.S.N.; Akhaury, S.B. (Ranchi Univ. (India). Dept. of Botany)

    1982-01-01

    A qualitative study of the mutants produced in M/sub 2/ generation has been made. The mutants were classified as: (1) chlorophyll mutant, (2) morphological mutant, (3) pollen mutant, (4) semi-sterile and (5) sterile mutant. Cytological investigations of pollen mutants, sterile and semi-sterile mutants have revealed that these mutants generally arise at higher dose levels (20 Kr and 25 Kr).

  9. Electrophoretic demonstration of glycoproteins, lipoproteins, and phosphoproteins in human and bovine enamel

    DEFF Research Database (Denmark)

    Kirkeby, S; Moe, D; Bøg-Hansen, T C;

    1990-01-01

    Enamel proteins from fully mineralized human molars and from bovine tooth germs were separated by electrophoresis. The gels were stained for detection of glycoproteins, lipoproteins, and phosphoproteins. Glycoproteins were shown by periodic acid-Schiff staining and lectin blotting. In mature human...... enamel a number of high molecular weight proteins could be demonstrated after ethylenediaminetetra-acetic acid demineralization and subsequent Triton X-100 extraction. These proteins are suggested to be lipoproteins. Phosphoproteins could only be visualized in enamel matrix from the tooth germs....

  10. Cholesteryl ester transfer activity. Localization and role in distribution of cholesteryl ester among lipoproteins in man.

    Science.gov (United States)

    Groener, J E; Van Rozen, A J; Erkelens, D W

    1984-03-01

    The cholesteryl ester exchange/transfer protein is involved in the transport of cholesteryl ester from high density lipoproteins (HDL) to very low density lipoproteins (VLDL) and low density lipoproteins (LDL). Localization of cholesteryl ester transfer activity (CETA) in plasma was studied by measuring CETA in various delipidated fractions from a single step density ultracentrifugation gradient of plasma. CETA was measured in an in vitro system by calculating the exchange of cholesteryl ester in a standard mixture of [3H]CE-HDL and LDL. The method used for the delipidation of plasmas and fractions to be tested was critical. Optimal results were obtained by delipidation with diisopropylether-butanol (60: 40, v/v) at O degrees C. The bulk of CETA was detected in HDL3 (1.125 less than d less than 1.210 g/ml) when the lipoproteins were separated by single-step density gradient ultracentrifugation and in the 'lipoprotein-free' fraction (d greater than 1.250 g/ml) when the lipoproteins were separated by flotation ultracentrifugation including two washes. To determine whether CETA plays a role in the distribution of cholesteryl ester among the various lipoproteins, it was measured in whole plasma from normal and hyperlipidemic subjects. Plasma was delipidated before the assay in order to prevent bias due to variation of cholesterol content. CETA was higher in delipidated plasma of hyperlipidemic subjects (117.3 +/- 36.5 nmol CE/ml/h) than in delipidated plasma of normolipidemic controls (68.7 +/- 17.6 nmol CE/ml/h) (P less than 0.005). A positive correlation (r = 0.80, P less than 0.005) was found between CETA and (VLDL + LDL) cholesterol levels. A negative correlation (r = 0.57, P less than 0.05) existed between CETA and HDL cholesterol. This correlation was found both in the group as a whole and within the normal and the hyperlipidemic groups separately. The activity of the cholesteryl ester transfer appears to be a regulatory factor in the distribution of cholesteryl

  11. A solid dietary fat containing fish oil redistributes lipoprotein subclasses without increasing oxidative stress in men

    DEFF Research Database (Denmark)

    Tholstrup, T.; Hellgren, Lars; Petersen, M.;

    2004-01-01

    by oleic acid in test fat "O." Plasma total triacylglycerol (TAG), VLDL TAG, cholesterol in VLDL, and intermediate density lipoproteins (IDL) were lower (P LDL-2 (d = 1031-1042 g/L) subclass, and cholesterol of HDL2b subclass, were higher after intake......, a solid dietary fat containing (n-3) PUFA decreased plasma TAG, VLDL, and IDL cholesterol, and redistributed lipoprotein subclasses in LDL and HDL, with a higher concentration of the larger and less atherogenic subfractions. These changes took place without an increase in oxidative stress as measured...

  12. Relationship between two common lipoprotein lipase variants and the metabolic syndrome and its individual components

    DEFF Research Database (Denmark)

    Vishram, Julie K K; Hansen, Tine W; Torp-Pedersen, Christian;

    2016-01-01

    BACKGROUND: Common lipoprotein lipase (LPL) variants are important determinants of triglycerides (TG) and high-density lipoprotein (HDL) cholesterol (C) concentrations. High TG/low HDL-C tend to cluster with hypertension, glucose intolerance, and abdominal obesity and comprise the metabolic...... syndrome (MetS). The role of LPL variants as a cause of MetS is unclear. This study investigated the relationship between two common LPL variants and the presence of MetS and its individual components. METHODS: Cross-sectional study, including 2348 Danish women (50.7%) and men, age 41-72 years, without...

  13. Transvascular low-density lipoprotein transport in patients with diabetes mellitus (type 2)

    DEFF Research Database (Denmark)

    Kornerup, Karen; Nordestgaard, Børge Grønne; Feldt-Rasmussen, Bo;

    2002-01-01

    accumulation and, thus, atherosclerosis. METHODS AND RESULTS: We developed an in vivo method for measurement of transvascular transport of low density lipoprotein (LDL) and applied it in 16 patients with maturity-onset diabetes (type 2) and 29 healthy control subjects. Autologous 131I-labeled LDL...... plasma insulin levels in diabetic patients. CONCLUSIONS: Transvascular LDL transport may be increased in patients with type 2 diabetes. This suggests that lipoprotein flux into the arterial wall is increased in people with diabetes, possibly explaining the accelerated development of atherosclerosis....... in patients with diabetes and control subjects, respectively (P2.5%/h and 5.3+/-1.6%/h (P

  14. NMR and interval PLS as reliable methods for determination of cholesterol in rodent lipoprotein fractions

    DEFF Research Database (Denmark)

    Kristensen, Mette; Savorani, Francesco; Ravn-Haren, Gitte;

    2010-01-01

    data and the NMR spectra, an interval partial least-square (iPLS) regression model to predict the amount of cholesterol in the different lipoprotein fractions was developed. The relative errors of the prediction models were between 12 and 33% and had correlation coefficients (r) between 0.96 and 0...... fractions in rat plasma is presented in this paper. Plasma from two rat studies (n = 68) was used in determining the lipoprotein profile by an established ultracentrifugation method and proton nuclear magnetic resonance (NMR) spectra of replicate samples was obtained. From the ultracentrifugation reference...

  15. Enzymatic Modification of Plasma Low Density Lipoproteins in Rabbits: A Potential Treatment for Hypercholesterolemia

    Science.gov (United States)

    Labeque, Regine; Mullon, Claudy J. P.; Ferreira, Joao Paulo M.; Lees, Robert S.; Langer, Robert

    1993-04-01

    Phospholipase A_2 (EC 3.1.1.4) hydrolyzes certain phospholipids of low density lipoprotein (LDL). Plasma clearance of phospholipase A_2-modified human LDL is up to 17 times faster than that of native human LDL in hypercholesterolemic rabbits. Modification of blood lipoproteins of hypercholesterolemic rabbits was performed by using an extracorporeal circuit containing immobilized phospholipase A_2. After 90-min treatments, nearly 30% decreases in plasma cholesterol concentrations were observed. Erythrocyte, leukocyte, and platelet counts showed no net change after treatment. This technique does not require any fluid replacement or sorbent regeneration and offers a potential approach for lowering serum cholesterol and LDL levels.

  16. Regulatory Effects of Fenofibrate and Atorvastatin on Lipoprotein A-I and Lipoprotein A-I:A-II Kinetics in the Metabolic Syndrome

    OpenAIRE

    Chan, Dick C.; Watts, Gerald F.; Ooi, Esther M.M.; Rye, Kerry-Anne; Ji, Juying; Johnson, Anthony G.; Barrett, P Hugh R

    2009-01-01

    OBJECTIVE Subjects with the metabolic syndrome have reduced HDL cholesterol concentration and altered metabolism of high-density lipoprotein (Lp)A-I and LpA-I:A-II particles. In the metabolic syndrome, fenofibrate and atorvastatin may have differential effects on HDL particle kinetics. RESEARCH DESIGN AND METHODS Eleven men with metabolic syndrome were studied in a randomized, double-blind, crossover trial of 5-week intervention periods with placebo, fenofibrate (200 mg/day), and atorvastatin...

  17. [Possibility of New Circulating Atherosclerosis-Related Lipid Markers Measurement in Medical and Complete Medical Checkups: Small Dense Low-Density Lipoprotein Cholesterol and Lipoprotein Lipase].

    Science.gov (United States)

    Sumino, Hiroyuki; Nakajima, Katsuyuki; Murakami, Masami

    2016-03-01

    Small dense low-density lipoprotein cholesterol (sdLDL-C) concentrations correlate more strongly with cardiovascular disease (CVD) than other LDL-C and large LDL particle concentrations. Lipoprotein lipase (LPL) plays a central role in triglyceride-rich lipoprotein metabolism by catalyzing the hydrolysis of triglycerides in chylomicrons and very low-density lipoprotein particles and is a useful biomarker in diagnosing Type I, Type IV, and Type V hyperlipidemia. Therefore, the measurement of circulating sdLDL-C and LPL concentrations contributes to the assessment of circulating atherosclerosis-related lipid markers. However, the measurement of these lipids has not been fully adopted in medical and complete medical checkups. Recently, novel automated homogenous assay for measuring sdLDL-C and latex particle-enhanced turbidimetric immunoassay (LTIA) for measuring LPL have been developed, respectively. Using these new assays, sdLDL-C values showed excellent agreement with those obtained by isolation of the d = 1.044 - 1.063 g/mL plasma fraction by sequential ultracentrifugation, and LPL values measured with and without heparin injection were highly correlated with the values measured by the LPL-enzyme-linked immunosorbent assay (ELISA). These assays may be superior to the previous assays for the measurement of sdLDL-C and LPL concentrations due their simplicity and reproducibility. The measurements of sdLDL-C and LPL concentrations may be useful as lipid markers in the assessment of the development and progression of atherosclerosis and the detection of pathological conditions and diseases if these markers are measured in medical and complete medical checkups. We have introduced the possibility of the novel measurement of circulating atherosclerosis-related lipid markers such as sdLDL-C and LPL in medical and complete medical checkups. Further studies are needed to clarify whether sdLDL-C and LPL concentrations are related to the development and progression of

  18. Surface-Associated Lipoproteins Link Enterococcus faecalis Virulence to Colitogenic Activity in IL-10-Deficient Mice Independent of Their Expression Levels.

    Science.gov (United States)

    Ocvirk, Soeren; Sava, Irina G; Lengfelder, Isabella; Lagkouvardos, Ilias; Steck, Natalie; Roh, Jung H; Tchaptchet, Sandrine; Bao, Yinyin; Hansen, Jonathan J; Huebner, Johannes; Carroll, Ian M; Murray, Barbara E; Sartor, R Balfour; Haller, Dirk

    2015-06-01

    The commensal Enterococcus faecalis is among the most common causes of nosocomial infections. Recent findings regarding increased abundance of enterococci in the intestinal microbiota of patients with inflammatory bowel diseases and induction of colitis in IL-10-deficient (IL-10-/-) mice put a new perspective on the contribution of E. faecalis to chronic intestinal inflammation. Based on the expression of virulence-related genes in the inflammatory milieu of IL-10-/- mice using RNA-sequencing analysis, we characterized the colitogenic role of two bacterial structures that substantially impact on E. faecalis virulence by different mechanisms: the enterococcal polysaccharide antigen and cell surface-associated lipoproteins. Germ-free wild type and IL-10-/- mice were monoassociated with E. faecalis wild type OG1RF or the respective isogenic mutants for 16 weeks. Intestinal tissue and mesenteric lymph nodes (MLN) were collected to characterize tissue pathology, loss of intestinal barrier function, bacterial adhesion to intestinal epithelium and immune cell activation. Bone marrow-derived dendritic cells (BMDC) were stimulated with bacterial lysates and E. faecalis virulence was additionally investigated in three invertebrate models. Colitogenic activity of wild type E. faecalis (OG1RF score: 7.2±1.2) in monoassociated IL-10-/- mice was partially impaired in E. faecalis lacking enterococcal polysaccharide antigen (ΔepaB score: 4.7±2.3; pManduca sexta larvae and impaired penetration into the colonic mucus layer of IL-10-/- mice. Lipoprotein-deficient E. faecalis exhibited an impaired TLR2-mediated activation of BMDCs in vitro despite their ability to fully reactivate MLN cells as well as MLN-derived colitogenic T cells ex vivo. E. faecalis virulence factors accounting for bacterial adhesion to mucosal surfaces as well as intestinal barrier disruption partially contribute to colitogenic activity of E. faecalis. Beyond their well-known role in infections, cell surface

  19. Plasma Lipoprotein-associated Phospholipase A(2) Is Inversely Correlated with Proprotein Convertase Subtilisin-kexin Type 9

    NARCIS (Netherlands)

    Constantinides, Alexander; Kappelle, Paul J. W. H.; Lambert, Gilles; Dullaart, Robin P. F.

    2012-01-01

    Background and Aims. Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is a proatherogenic phospholipase A(2), which is predominantly complexed to low-density lipoprotein (LDL) particles. Proprotein convertase subtilisin-kexin type 9 (PCSK9) provides a key step in LDL metabolism by stimulating L

  20. Serum apolipoprotein(a) levels and its effect on the measured values of low density lipoprotein cholesterol.

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    Serum low density lipoprotein cholesterl (LDL-C) and lipoprotein(a)[Lp(a)]levels were analyzed in 1032 sequential cases on routine physical check up, with special attention to the effect of Lp(a) on the LDL-C values. Since the determination of LDL-C by various

  1. Surface-associated lipoprotein PpmA of Streptococcus pneumoniae is involved in colonization in a strain-specific manner.

    NARCIS (Netherlands)

    Cron, L.E.; Bootsma, H.J.; Noske, N.; Burghout, P.J.; Hammerschmidt, S.; Hermans, P.W.M.

    2009-01-01

    Streptococcus pneumoniae produces two surface-associated lipoproteins that share homology with two distinct families of peptidyl-prolyl isomerases (PPIases), the streptococcal lipoprotein rotamase A (SlrA) and the putative proteinase maturation protein A (PpmA). Previously, we have demonstrated that

  2. Moderate alcohol consumption and changes in postprandial lipoproteins of premenopausal and postmenopausal women : a diet-controlled, randomized intervention study

    NARCIS (Netherlands)

    Gaag, van der M.S.; Sierksma, A.; Schaafsma, G.; Bakker, M.; Hendriks, J.F.J.

    2000-01-01

    Moderate alcohol consumption is associated with a reduced risk of coronary heart disease. Earlier studies in men have shown that moderate alcohol consumption affects lipoprotein metabolism and hemostasis. In this diet-controlled, randomized, crossover trial, we investigated the effect on lipoprotein

  3. Elevated plasma cholesteryl ester transfer in NIDDM : relationships with apolipoprotein B-containing lipoproteins and phospholipid transfer protein

    NARCIS (Netherlands)

    Riemens, S; van Tol, A; Sluiter, W; Dullaart, R

    1998-01-01

    Lecithin:cholesteryl acyl transferase (LCAT) and cholesteryl ester transfer protein (CETP) are key factors in the esterification of cholesterol and the subsequent transfer of cholesteryl ester from high density lipoproteins (HDL) towards very low and low density lipoproteins (VLDL + LDL). Phospholip

  4. Sort1, encoded by the cardiovascular risk locus 1p13.3, is a regulator of hepatic lipoprotein export

    DEFF Research Database (Denmark)

    Kjølby, Mads Fuglsang; Andersen, Olav Michael; Breiderhoff, Tilman;

    2010-01-01

    receptor for apolipoprotein (apo) B100. It interacts with apoB100 in the Golgi and facilitates the formation and hepatic export of apoB100-containing lipoproteins, thereby regulating plasma low-density lipoprotein (LDL) cholesterol. Absence of sortilin in gene-targeted mice reduces secretion...

  5. Lipoprotein interactions with a polyurethane and a polyethylene oxide-modified polyurethane at the plasma-material interface.

    Science.gov (United States)

    Cornelius, Rena M; Macri, Joseph; Cornelius, Katherine M; Brash, John L

    2016-01-01

    Lipoproteins [high density lipoprotein (HDL), low density lipoprotein (LDL), and very low density lipoprotein (VLDL)] are present in blood in relatively high concentrations, and, given their importance in cardiovascular disease, the interactions of these species with blood contacting biomaterials and their possible role in thrombogenesis is of interest. In the present communication, quantitative data on the adsorption of apolipoprotein AI, apolipoprotein AII (the main protein components of HDL), and apolipoprotein B (the main protein component of LDL and VLDL), as well as the lipoproteins themselves from plasma to a biomedical grade polyurethane (PU) with and without a copolymer additive that contains polyethylene oxide (PEO) segments, were investigated. Adsorption from some binary solutions was also studied. Significant quantities of the apolipoproteins were found to adsorb from plasma to the PU, while adsorption to the PEO material was more than 90% lower, demonstrating strong protein resistance of the latter material. In contrast, significant quantities of the lipoproteins were found to adsorb to the PEO as well as to the PU material. From these and previously published results, it is concluded that the protein layer formed on the PU surface from plasma (and by extension from blood) contains apolipoproteins and lipoproteins in addition to other plasma proteins; the layer formed on the PEO surface, however, appears to contain minimal quantities of plasma proteins (including free apolipoproteins) but significant quantities of lipoproteins. PMID:27306077

  6. A Splice Region Variant in LDLR Lowers Non-high Density Lipoprotein Cholesterol and Protects against Coronary Artery Disease

    NARCIS (Netherlands)

    Gretarsdottir, S.; Helgason, H.; Helgadottir, A.; Sigurdsson, A.; Thorleifsson, G.; Magnusdottir, A.; Oddsson, A.; Steinthorsdottir, V.; Rafnar, T.; Graaf, J. de; Daneshpour, M.S.; Hedayati, M.; Azizi, F.; Grarup, N.; Jorgensen, T.; Vestergaard, H.; Hansen, T.; Eyjolfsson, G.; Sigurdardottir, O.; Olafsson, I.; Kiemeney, B.; Pedersen, O.; Sulem, P.; Thorgeirsson, G.; Gudbjartsson, D.F.; Holm, H.; Thorsteinsdottir, U.; Stefansson, K.

    2015-01-01

    Through high coverage whole-genome sequencing and imputation of the identified variants into a large fraction of the Icelandic population, we found four independent signals in the low density lipoprotein receptor gene (LDLR) that associate with levels of non-high density lipoprotein cholesterol (non

  7. DMPD: The oxidation of lipoproteins by monocytes-macrophages. Biochemical andbiological mechanisms. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 10473535 The oxidation of lipoproteins by monocytes-macrophages. Biochemical andbio.... (.png) (.svg) (.html) (.csml) Show The oxidation of lipoproteins by monocytes-macrophages. Biochemical and...onocytes-macrophages. Biochemical andbiological mechanisms. Authors Chisolm GM 3rd, Hazen SL, Fox PL, Cathca

  8. Effect of 6 dietary fatty acids on the postprandial lipid profile, plasma fatty acids, lipoprotein lipase, and cholesterol ester transfer activities in healthy young men

    DEFF Research Database (Denmark)

    Tholstrup, T.; Sandstrøm, B.; Bysted, Anette;

    2001-01-01

    Background: There is increasing evidence that postprandial triacylglycerol-rich lipoproteins may be related to atherogenic risk. Objective: The objective was to investigate the effect of individual fatty acid intakes on postprandial plasma lipoprotein triacylglycerol and cholesterol concentrations...

  9. Interaction of peptide-bound beads with lipopolysaccharide and lipoproteins.

    Science.gov (United States)

    Suzuki, Masatsugu M; Matsumoto, Megumi; Omi, Hiroyuki; Kobayashi, Tomomi; Nakamura, Akio; Kishi, Hiroko; Kobayashi, Sei; Takagi, Takashi

    2014-05-01

    A-I and apoA-II are components of high density lipoprotein (HDL). Thus, it is likely that the P-beads-bound LPS was sequestered by HDL, resulting in neutralization of its toxicity. This study showed that by using P-beads, free LPS in plasma can be quantitatively measured by the LAL assay at a concentration of 1pg/mL. PMID:24632519

  10. Selective isolation of UV-sensitive Rhodopseudomonas sphaeroides mutants

    International Nuclear Information System (INIS)

    Application of penicillin selection method after UV irradiation (λ=254 nm) increases by an order efficiency of mutant selection sensible to ulraviolet radiation (uvs mutants), phototrophic bacterium Rhodopseudomonas sphaeroides induced with nitrosomethylurea (NMM). Over 30% of uvs mutants produced by means of this method possessed increased sensitivity not only to short-wave (sUV, λ=254 nm) but also to long-wave (lUV, λ>280 nm) UV radiations. No correlation in the degree of sensitivity of uvs mutants to sUV and lUV irradiations is discovered. Mutants, which are high-sensitive to lethal effect of lUV, are separated

  11. Model of mouth-to-mouth transfer of bacterial lipoproteins through inner membrane LolC, periplasmic LolA, and outer membrane LolB

    OpenAIRE

    Okuda, Suguru; Tokuda, Hajime

    2009-01-01

    Outer membrane-specific lipoproteins in Escherichia coli are released from the inner membrane by an ATP-binding cassette transporter, the LolCDE complex, which causes the formation of a soluble complex with a periplasmic molecular chaperone, LolA. LolA then transports lipoproteins to the outer membrane where an outer membrane receptor, LolB, incorporates lipoproteins into the outer membrane. The molecular mechanisms underlying the Lol-dependent lipoprotein sorting have been clarified in detai...

  12. Using of AFLP to evaluate gamma-irradiated amaranth mutants

    Directory of Open Access Journals (Sweden)

    Labajová Mária

    2013-01-01

    Full Text Available To determine which of several gamma-irradiated mutants of amaranth Ficha cultivar and K-433 hybrid are most genetically similar to their non-irradiated control genotypes, we performed amplified fragment length polymorphism (AFLP based analysis. A total of 40 selective primer combinations were used in reported analyses. First analyses of gamma-irradiated amaranth mutant lines were done used the AFLP. In the study, primers with the differentiation ability for all analysed mutant lines are reported. The very specific changes in the mutant lines´ non-coding regions based on AFLP length polymorphism were analysed. Mutant lines of the Ficha cultivar (C15, C26, C27, C82, C236 shared a genetic dissimilarity of 0,11 and their ISSR profiles are more similar to the Ficha than those of K-433 hybrid mutant lines. The K-433 mutant lines (D54, D279, D282 shared genetic dissimilarity of 0,534 but are more distinct to their control plant as a whole, as those of the Ficha mutant lines. Different AFLP fingerprints patters of the mutant lines when compared to the Ficha cultivar and K-433 hybrid AFLP profiles may be a consequence of the complex response of the intergenic space of mutant lines to the gamma-radiance. Although a genetic polymorphism was detected within accessions, the AFLP markers successfully identified all the accessions. The AFLP results are discussed by a combination of biochemical characteristics of mutant lines and their control genotypes.

  13. A photorespiratory mutant of Chlamydomonas reinhardtii

    International Nuclear Information System (INIS)

    A mutant strain of Chlamydomonas reinhardtii, designated 18-7F, has been isolated and characterized. 18-7F requires a high CO2 concentration for photoautrophic growth in spite of the apparent induction of a functional CO2 concentrating mechanism in air-adapted cells. In 2% O2 the photosynthetic characteristics of 18-7F and wild type are similar. In 21% O2, photosynthetic O2 evolution is severely inhibited in the mutant by preillumination in limiting CO2, although the apparent photosynthetic affinity for inorganic carbon is similar in preilluminated cells and in cells incubated in the dark prior to O2 evolution measurements. Net CO2 uptake is also inhibited when the cells are exposed to air (21% O2, 0.035% CO2, balance N2) for longer than a few minutes. [14C]Phosphoglycolate accumulates within 5 minutes of photosynthetic 14CO2 fixation in cells of 18-7F. Phosphoglycolate does not accumulate in wild type. Phosphoglycolate phosphatase activity in extracts from air-adapted cells of 18-7F is 10 to 20% of that in wild-type Chlamydomonas. The activity of phosphoglycolate phosphatase in heterozygous diploids is intermediate between that of homozygous mutant and wild-type diploids. It was concluded that the high-CO2 requiring phenotype in 18-7F results from a phosphoglycolate phosphatase deficiency. Genetic analyses indicate that this deficiency results from a single-gene, nuclear mutation. We have named the locus pgp-1

  14. Association between moderately oxidized low-density lipoprotein and high-density lipoprotein particle subclass distribution in hemodialyzed and post-renal transplant patients

    Institute of Scientific and Technical Information of China (English)

    El(z)bieta KIMAK; Magdalena HA(L)ABI(S); Iwona BARANOWICZ-GA SZCZYK; Janusz SOLSKI; Andrzej KSIA(Z)EK

    2011-01-01

    Disturbances in the metabolism of lipoprotein profiles and oxidative stress in hemodialyzed (HD) and post-renal transplant (Tx) patients are proatherogenic, but elevated concentrations of plasma high-density lipoprotein (HDL) reduce the risk of cardiovascular disease. We investigated the concentrations of lipid, lipoprotein, HDL particle,oxidized low-density lipoprotein (ox-LDL) and anti-ox-LDL, and paraoxonase-1 (PON-1) activity in HD (n=33) and Tx (n=71) patients who were non-smokers without active inflammatory disease, liver disease, diabetes, or malignancy.HD patients had moderate hypertriglyceridemia, normocholesterolemia, low HDL-C, apolipoprotein A-Ⅰ (apoA-Ⅰ) and HDL particle concentrations as well as PON-1 activity, and increased ox-LDL and anti-ox-LDL levels. Tx patients had hypertriglyceridemia, hypercholesterolemia, moderately decreased HDL-C and HDL particle concentrations and PON-1 activity, and moderately increased ox-LDL and anti-ox-LDL levels as compared to the reference, but ox-LDL and anti-ox-LDL levels and PON-1 activity were more disturbed in HD patients. However, in both patient groups, lipid and lipoprotein ratios (total cholesterol (TC)/HDL-C, LDL-C/HDL-C, triglyceride (TG)/HDL-C, HDL-C/non-HDL-C,apoA-Ⅰ/apoB, HDL-C/apoA-Ⅰ, TG/HDL) were atherogenic. The Spearman's rank coefficient test showed that the concentration of ox-LDL correlated positively with HDL particle level (R=0.363, P=0.004), and negatively with TC (R=-0.306, P=0.012), LDL-C (R=-0.283, P=0.020), and non-HDL-C (R=-0.263, P=0.030) levels in Tx patients. Multiple stepwise forward regression analysis in Tx patients demonstrated that ox-LDL concentration, as an independent variable, was associated significantly positively with HDL particle level. The results indicated that ox-LDL and decreased PON-1 activity in Tx patients may give rise to more mildly-oxidized HDLs, which are less stable, easily undergo metabolic remodeling, generate a greater number of smaller pre

  15. The P2Y2 receptor mediates uptake of matrix-retained and aggregated low density lipoprotein in primary vascular smooth muscle cells

    Science.gov (United States)

    Dissmore, Tixieanna; Seye, Cheikh I.; Medeiros, Denis M.; Weisman, Gary A.; Bardford, Barry; Mamedova, Laman

    2016-01-01

    Background and aims The internalization of aggregated low-density lipoproteins (agLDL) mediated by low-density lipoprotein receptor related protein (LRP1) may involve the actin cytoskeleton in ways that differ from the endocytosis of soluble LDL by the LDL receptor (LDLR). This study aims to define novel mechanisms of agLDL uptake through modulation of the actin cytoskeleton, to identify molecular targets involved in foam cell formation in vascular smooth muscle cells (VSMCs). The critical observation that formed the basis for these studies is that under pathophysiological conditions, nucleotide release from blood-derived and vascular cells activates SMC P2Y2 receptors (P2Y2Rs) leading to rearrangement of the actin cytoskeleton and cell motility. Therefore, we tested the hypothesis that P2Y2R activation mediates agLDL uptake by VSMCs. Methods Primary VSMCs were isolated from aortas of wild type (WT) C57BL/6 and.P2Y2R−/− mice to investigate whether P2Y2R activation modulates LRP1 expression. Cells were transiently transfected with cDNA encoding a hemagglutinin-tagged (HA-tagged) WT P2Y2R, or a mutant P2Y2R that unlike the WT P2Y2R does not bind the cytoskeletal actin-binding protein filamin-A (FLN-A). Results P2Y2R activation significantly increased agLDL uptake, and LRP1 mRNA expression decreased in P2Y2R−/− VSMCs versus WT. SMCs, expressing P2Y2R defective in FLN-A binding, exhibit 3-fold lower LDLR expression levels than SMCs expressing WT P2Y2R, while cells transfected with WT P2Y2R show greater agLDL uptake in both WT and P2Y2R−/− VSMCs versus cells transfected with the mutant P2Y2R. Conclusions Together, these results show that both LRP1 and LDLR expression and agLDL uptake are regulated by P2Y2R in VSMCs, and that agLDL uptake due to P2Y2R activation is dependent upon cytoskeletal reorganization mediated by P2Y2R binding to FLN-A. PMID:27522265

  16. P48 Major Surface Antigen of Mycoplasma agalactiae Is Homologous to a malp Product of Mycoplasma fermentans and Belongs to a Selected Family of Bacterial Lipoproteins

    OpenAIRE

    Rosati, Sergio; Pozzi, Sarah; Robino, Patrizia; Montinaro, Barbara; Conti, Amedeo; Fadda, Manlio; Pittau, Marco

    1999-01-01

    A major surface antigenic lipoprotein of Mycoplasma agalactiae, promptly recognized by the host's immune system, was characterized. The mature product, P48, showed significant similarity and shared conserved amino acid motifs with lipoproteins or predicted lipoproteins from Mycoplasma fermentans, Mycoplasma hyorhinis, relapsing fever Borrelia spp., Bacillus subtilis, and Treponema pallidum.

  17. Direct Low Density Lipoprotein Cholesterol and Glycated Albumin Levels in Type 2 Diabetes Mellitus

    Science.gov (United States)

    Diabetes mellitus is a major risk factor for coronary heart disease (CHD), renal failure, retinopathy, and neuropathy. Lowering glycosylated hemoglobin (HbA1c) as well as low-density lipoprotein-cholesterol (LDL-C) have been associated with a decreased risk of these complications. The aim in this st...

  18. Glycated albumin and direct low density lipoprotein cholesterol levels in type 2 diabetes mellitus

    Science.gov (United States)

    Diabetes mellitus is a major risk factor for coronary heart disease (CHD), renal failure, retinopathy, and neuropathy. Lowering glycosylated hemoglobin (HbA1c) as well as low-density lipoprotein-cholesterol (LDL-C) has been associated with a decreased risk of these complications. We evaluated the ut...

  19. Effects of plant sterols and olive oil phenols on serum lipoproteins in humans

    NARCIS (Netherlands)

    Vissers, M.N.

    2001-01-01

    The studies described in this thesis investigated whether minor components from vegetable oils can improve health by decreasing cholesterol concentrations or oxidative modification of low-density-lipoprotein (LDL) particles.The plant sterolsβ-sitosterol and sitostanol are known to decrease cholester

  20. Evaluation of the immediate vascular stability of lipoprotein lipase-generated 2-monoacylglycerol in mice

    DEFF Research Database (Denmark)

    Kleberg, Karen; Nielsen, Louise Lundeman; Stuhr-Hansen, Nicolai;

    2014-01-01

    2-Monoacylglycerols are gaining increasing interest as signaling lipids, beyond endocannabinoids, for example, as ligands for the receptor GPR119 and as mediators of insulin secretion. In the vascular system, they are formed by the action of lipoprotein lipase (LPL); however, their further dispos...

  1. Application of directly coupled HPLC MMR to separation and characterization of lipoproteins from human serum

    DEFF Research Database (Denmark)

    Daykin, C. A.; Corcoran, O.; Hansen, S. H.;

    2001-01-01

    with plasma proteins such as albumin occurred, and this clearly limits quantitation of that species by HPLC peak integration. We also show, for the first time, the application of directly coupled HPLC H-1 NMR spectroscopy to confirm the identification of the three major lipoproteins, The full chromatographic...... by the HPLC separation and that their gross supramolecular organization was intact....

  2. Genetic analysis of long-lived families reveals novel variants influencing high density-lipoprotein cholesterol

    DEFF Research Database (Denmark)

    Feitosa, Mary F; Wojczynski, Mary K; Straka, Robert;

    2014-01-01

    The plasma levels of high-density lipoprotein cholesterol (HDL) have an inverse relationship to the risks of atherosclerosis and cardiovascular disease (CVD), and have also been associated with longevity. We sought to identify novel loci for HDL that could potentially provide new insights...

  3. Total and High-Density Lipoprotein Cholesterol in Adults with Mental Retardation.

    Science.gov (United States)

    Rimmer, James H.; Kelly, Luke E.

    1990-01-01

    The study evaluated the total cholesterol and high density lipoprotein cholesterol of 40 adults (mean age 37.5 years) with mental retardation residing at an intermediate care facility. Results indicated that 59 percent of the males and 68 percent of the females were at moderate to high risk for coronary heart disease. (DB)

  4. Phenotype of heterozygotes for low-density lipoprotein receptor mutations identified in different background populations

    DEFF Research Database (Denmark)

    Tybjaerg-Hansen, Anne; Jensen, Henrik Kjaerulf; Benn, Marianne;

    2005-01-01

    The effect of mutations on phenotype is often overestimated because of ascertainment bias. We determined the effect of background population on cholesterol phenotype associated with specific mutations in the low-density lipoprotein (LDL) receptor and the relative importance of background populati...

  5. Pentanucleotide repeat polymorphism, lipoprotein(a) levels, and risk of ischemic heart disease

    DEFF Research Database (Denmark)

    Kamstrup, P.R.; Tybjaerg-Hansen, A.; Steffensen, R.;

    2008-01-01

    predicts elevated lipoprotein(a) levels and risk of myocardial infarction (MI) and ischemic heart disease (IHD) in the general population. DESIGN: We used a cohort study of the Danish general population, The Copenhagen City Heart Study, including 10,276 individuals of which 860 and 1,781 developed MI...

  6. Fractionation of human serum lipoproteins and simultaneous enzymatic determination of cholesterol and triglycerides

    Energy Technology Data Exchange (ETDEWEB)

    Qureshi, Rashid Nazir [Polymer-Analysis Group, van' t Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018WV Amsterdam (Netherlands); Kok, Wim Th., E-mail: W.Th.Kok@uva.nl [Polymer-Analysis Group, van' t Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018WV Amsterdam (Netherlands); Schoenmakers, Peter J. [Polymer-Analysis Group, van' t Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018WV Amsterdam (Netherlands)

    2009-11-03

    A method based on Asymmetric Flow Field-Flow Fractionation (AF4) was developed to separate different types of lipoproteins from human serum. The emphasis in the method optimization was on the possibilities to characterize the largest lipoprotein fractions (LDL and VLDL), which is usually not possible with the size-exclusion chromatography methods applied in routine analysis. Different channel geometries and flow programs were tested and compared. The use of a short fractionation channel was shown to give less sample dilution at the same fractionation power compared to a conventional, long channel. Different size selectivities were obtained with an exponential decay and a linear cross flow program. The ratio of the UV absorption signal to the light scattering signal was used to validate the relation between retention time and size of the fractionated particles. An experimental setup was developed for the simultaneous determination of the cholesterol and triglycerides distribution over the lipoprotein fractions, based on enzymatic reactions followed by UV detection at 500 nm. Coiled and knitted PTFE tubing reactors were compared. An improved peak sharpness and sensitivity were observed with the knitted tubing reactor. After optimization of the experimental conditions a satisfactory linearity and precision (2-3% rsd for cholesterol and 5-6% rsd for triglycerides) were obtained. Finally, serum samples, a pooled sample from healthy volunteers and samples of sepsis patients, were analyzed with the method developed. Lipoprotein fractionation and cholesterol and triglyceride distributions could be correlated with the clinical background of the samples.

  7. Low-density lipoprotein-lowering strategies: target versus maximalist versus population percentile.

    NARCIS (Netherlands)

    Sniderman, A.D.; Graaf, J. de; Couture, P.

    2012-01-01

    PURPOSE OF REVIEW: Maximalist low-density lipoprotein (LDL)-lowering strategies such as lowering LDL as much as possible or, alternatively, using the most potent LDL-lowering regimens have become increasingly popular. Almost all attention has focused on the potential advantages of these approaches w

  8. Cigarette smoking and its association with serum lipid/lipoprotein among Chinese nonagenarians/centenarians

    Directory of Open Access Journals (Sweden)

    Yan-Ling Zhang

    2012-07-01

    Full Text Available Abstract Objective Cigarette smoking had been confirmed as an increased risk for dyslipidemia, but none of the evidence was from long-lived population. In present study, we detected relationship between cigarette smoking habits and serum lipid/lipoprotein (serum Triglyceride (TG, Total cholesterol (TC, Low-density lipoprotein (LDL and high-density lipoprotein (HDL among Chinese Nonagenarians/Centenarian. Methods The present study analyzed data from the survey that was conducted on all residents aged 90 years or more in a district, there were 2,311,709 inhabitants in 2005. Unpaired Student’s t test, χ2 test, and multiple logistic regression were used to analyze datas. Results The individuals included in the statistical analysis were 216 men and 445 women. Current smokers had lower level of TC (4.05 ± 0.81 vs. 4.21 ± 0.87, t = 2.403, P = 0.017 and lower prevalence of hypercholesteremia (9.62% vs. 15.13%, χ2 = 3.018,P = 0.049 than nonsmokers. Unadjusted and adjusted multiple logistic regressions showed that cigarette smoking was not associated with risk for abnormal serum lipid/lipoprotein. Conclusions In summary, we found that among Chinese nonagenarians/centenarians, cigarette smoking habits were not associated with increased risk for dyslipidemia, which was different from the association of smoking habits with dyslipidemia in general population.

  9. A Modified Chitosan Adsorbent for Selective Removal of Low Density Lipoprotein

    Institute of Scientific and Technical Information of China (English)

    Guo Qi FU; Ke Yu SHI; Zhi YUAN; Wen Qiang NIU; Bing Lin HE; Bin LIU; Bin SHEN; Yan LIU

    2004-01-01

    A modified chitosan adsorbent was synthesized through a simple preparation procedure, and it demonstrated good adsorption performance for selective removal of low density lipoprotein in human plasma. Phase inversion technique was employed to form chitosan beads, to which epoxy groups were then introduced by reacting with ethyleneglycol diglycidylether, and tryptophan was subsequently coupled to the epoxy-activated beads.

  10. Effect of dietary cis and trans fatty acids on serum lipoprotein(a) levels in humans.

    NARCIS (Netherlands)

    Mensink, R.P.; Zock, P.L.; Katan, M.B.; Hornstra, G.

    1992-01-01

    Serum lipoprotein[a] (Lp[a]) is a strong risk factor for coronary heart disease. We therefore examined the effect of dietary fatty acid composition on serum Lp[a] levels in three strictly controlled experiments with healthy normocholesterolemic men and women. In Expt. I, 58 subjects consumed a contr

  11. PLASMA-LIPOPROTEINS AND RENAL APOLIPOPROTEINS IN RATS WITH CHRONIC ADRIAMYCIN NEPHROSIS

    NARCIS (Netherlands)

    JOLES, JA; VANTOL, A; JANSEN, EHJM; KOOMANS, HA; RABELINK, TJ; VANGOOR, H

    1993-01-01

    The relation between plasma lipoprotein composition and renal apolipoprotein deposition was studied in nephrotic rats in which stable renal function had been monitored for 7 months after a single low dose of adriamycin (ADR, 3 mg/kg). Proteinuria was observed 3 weeks after ADR and increased progress

  12. Lipoprotein glomerulopathy: a case report of a rare disease in a brazilian child

    Directory of Open Access Journals (Sweden)

    Karla Lais Pegas

    2014-03-01

    Full Text Available Lipoprotein glomerulopathy (LPG is a rare autosomal recessive glomerulopathy associated with the deposition of lipoprotein thrombi in the capillary lumina due to apoE gene mutations. Abnormal plasma lipoprotein profile and marked increase in serum apoliprotein E (apoE are characteristic clinical data. The compromised patients can present nephrotic syndrome, hematuria, and progressive renal failure. Herein, the authors present the first described case of LPG in a Brazilian male patient, 11 years, who presented with a steroid-resistant nephrotic syndrome. Renal function was normal. Kidney biopsy showed markedly enlarged glomerulus, with dilated capillary loops and weak eosinophilic lipoprotein thrombi in the capillary lumina. Interstitium, tubules, arteries, and veins showed normal histologic aspect. Genotypic study for the apoE gene showed the presence of the alleles E3 and E4. The diagnosis of LPG was then performed. The patient received lipid-lowering treatment. After 2 years of follow-up, renal function is gradually decreasing, with persisting heavy proteinuria, despite a marked decrease in serum cholesterol and triglycerides levels.

  13. Lipoprotein Subfractions in Metabolic Syndrome and Obesity: Clinical Significance and Therapeutic Approaches

    Directory of Open Access Journals (Sweden)

    Manfredi Rizzo

    2013-03-01

    Full Text Available Small, dense low density lipoprotein (sdLDL represents an emerging cardiovascular risk factor, since these particles can be associated with cardiovascular disease (CVD independently of established risk factors, including plasma lipids. Obese subjects frequently have atherogenic dyslipidaemia, including elevated sdLDL levels, in addition to elevated triglycerides (TG, very low density lipoprotein (VLDL and apolipoprotein-B, as well as decreased high density lipoprotein cholesterol (HDL-C levels. Obesity-related co-morbidities, such as metabolic syndrome (MetS are also characterized by dyslipidaemia. Therefore, agents that favourably modulate LDL subclasses may be of clinical value in these subjects. Statins are the lipid-lowering drug of choice. Also, anti-obesity and lipid lowering drugs other than statins could be useful in these patients. However, the effects of anti-obesity drugs on CVD risk factors remain unclear. We review the clinical significance of sdLDL in being overweight and obesity, as well as the efficacy of anti-obesity drugs on LDL subfractions in these individuals; a short comment on HDL subclasses is also included. Our literature search was based on PubMed and Scopus listings. Further research is required to fully explore both the significance of sdLDL and the efficacy of anti-obesity drugs on LDL subfractions in being overweight, obesity and MetS. Improving the lipoprotein profile in these patients may represent an efficient approach for reducing cardiovascular risk.

  14. Moderate alcohol consumption and lipoprotein-associated phospholipase A2 activity

    NARCIS (Netherlands)

    Beulens, J.W.J.; Berg, van den R.; Kok, F.J.; Helander, A.; Vermunt, S.H.F.; Hendriks, H.F.J.

    2008-01-01

    Background and aims To investigate the effect of moderate alcohol consumption on lipoprotein-associated phospholipase A2 activity, markers of inflammation and oxidative stress and whether these effects are modified by BMI. Methods and results Eleven lean (BMI: 18.5¿25 kg/m2) and 9 overweight (BMI &g

  15. Changes in the triglyceride-rich lipoproteins and the response to dietary cholesterol in man.

    NARCIS (Netherlands)

    Demacker, P.N.M.; Glatz, J.F.C.; Katan, M.B.

    1988-01-01

    The effect of a cholesterol-enriched diet was studied in nine healthy volunteers with special emphasis to the changes which occurred in the triglyceride-rich lipoproteins (d<1.019 g/ml). Compared to the habitual diet, a moderately increased intake of cholesterol (from 300–900 mg/day) resulted in cha

  16. Variability in lipoprotein concentrations in serum after prolonged storage at -20°C.

    NARCIS (Netherlands)

    Tiedink, H.G.M.; Katan, M.B.

    1989-01-01

    The effects of freezing and storage at − 20° C of serum on the measurement of cholesterol and triglycerides concentrations in lipoprotein fractions separated by density gradient ultracentrifugation were investigated. Fresh, fasting, normolipidemic sera from 24 healthy individuals were divided into a

  17. Lipid, lipoprotein, and apolipoprotein profiles in active and sedentary men with tetraplegia

    NARCIS (Netherlands)

    Dallmeijer, A J; Hopman, M T; van der Woude, L H

    1997-01-01

    OBJECTIVE: To investigate whether the risk profile of coronary heart disease (CHD) is more favorable in physically active men with tetraplegia compared with sedentary men with tetraplegia. DESIGN: Using a cross-sectional design, the lipid and (apo)lipoprotein concentrations of 11 active and 13 seden

  18. Alcohol-extracted, but not intact, dietary soy protein lowers lipoprotein(a) markedly

    DEFF Research Database (Denmark)

    Meinertz, Hans; Nilausen, Karin; Hilden, Jørgen

    2002-01-01

    We previously found that dietary soy protein produces higher lipoprotein(a) [Lp(a)] plasma concentrations than does casein. This study tested the hypothesis that soy protein contains Lp(a)-raising alcohol-removable components. Twelve normolipidemic women and men consumed, in a crossover design, l...

  19. Lipoprotein-associated phospholipase A2 and coronary calcification - The Rotterdam coronary calcification study

    NARCIS (Netherlands)

    Kardys, Isabella; Oei, Hok-Hay S.; Hofman, Albert; Oudkerk, Matthijs; Witteman, Jacqueline C. M.

    2007-01-01

    Objectives: Although several studies have recently suggested that lipoprotein-associated phospholipase A2 (Lp-PLA2) is an independent predictor of coronary events, only one study has examined the association between Lp-PLA2 and coronary calcification, using young adults. We investigated the associat

  20. Effect of a Marathon Run on Serum Lipoproteins, Creatine Kinase, and Lactate Dehydrogenase in Recreational Runners

    Science.gov (United States)

    Kobayashi, Yoshio; Takeuchi, Toshiko; Hosoi, Teruo; Yoshizaki, Hidekiyo; Loeppky, Jack A.

    2005-01-01

    The objective of this study was to determine the effect of a marathon run on serum lipid and lipoprotein concentrations and serum muscle enzyme activities and follow their recovery after the run. These blood concentrations were measured before, immediately after, and serially after a marathon run in 15 male recreational runners. The triglyceride…

  1. Cellular uptake of lipoproteins and Persistent Organic Compounds - An update and new data

    DEFF Research Database (Denmark)

    Hjelmborg, Philip Sebastian; Andreassen, Thomas Kjærgaard; Bonefeld-Jørgensen, Eva Cecilie

    2008-01-01

     There are a number of interactions related to transport of lipophilic xenobiotic compounds in the blood stream of mammals. This paper will focus on the interactions between lipoproteins and persistent organic pollutants (POPs) and how these particles are taken up by cells. A number of POPs...

  2. Effect of losartan and spironolactone on triglyceride-rich lipoproteins in diabetic nephropathy

    Science.gov (United States)

    Srivastava, Anand; Adams-Huet, Beverley; Vega, Gloria L; Toto, Robert D

    2016-01-01

    Angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARBs) can improve dyslipidemia in patients with diabetes and albuminuria. Whether combined ACEi+ARB or ACEi+mineralocorticoid receptor blockade improves dyslipidemia is not known. We hypothesized long-term administration of either losartan 100 mg or spironolactone 25 mg once daily added onto lisinopril 80 mg once daily would improve dyslipidemia in diabetic nephropathy (DN). We measured lipid levels, very-low-density (V), intermediate-density (I), low-density (LDL), high-density (HDL) lipoprotein, LDL particle size with their respective cholesterol (C) and apolipoprotein B levels (ApoB), and urine albumin/creatinine ratio (UACR) at 12-week interval during a 48-week randomized, double-blind placebo-controlled trial in 81 patients with DN. Plasma lipids and lipoprotein C were analyzed enzymatically and Apo B was determined chemically. Data were analyzed by mixed model repeated measures. ΔUACR differed among treatment arms (placebo −24.6%, los −38.2%, spiro −51.6%, p=0.02). No correlation existed between ΔUACR and ΔTG or any of the lipid or lipoprotein measurements. Compared with placebo losartan, but not spironolactone, decreased TG (−20.9% vs +34.3%, pdyslipidemia in patients with DN. We speculate the mechanism improved clearance of VLDL and remnant lipoproteins. Trial registration number NCT00381134; Results. PMID:27388615

  3. Comparison of Total Antioxidant Capacity Oxidative Stress and Blood Lipoprotein Parameters in Volleyball Players and Sedentary

    Science.gov (United States)

    Gokhan, Ismail

    2013-01-01

    This study aims to measure, then compare sedentary blood lipoproteins, oxidant- antioxidant state and oxidative stress index in volleyball players. The experimental group of the research consists of regularly practising 20 boys between the ages of 12 and 17, and the control group comprises 32 children practising no particular sports branch, 12 of…

  4. ApoC-III inhibits clearance of triglyceride-rich lipoproteins through LDL family receptors.

    Science.gov (United States)

    Gordts, Philip L S M; Nock, Ryan; Son, Ni-Huiping; Ramms, Bastian; Lew, Irene; Gonzales, Jon C; Thacker, Bryan E; Basu, Debapriya; Lee, Richard G; Mullick, Adam E; Graham, Mark J; Goldberg, Ira J; Crooke, Rosanne M; Witztum, Joseph L; Esko, Jeffrey D

    2016-08-01

    Hypertriglyceridemia is an independent risk factor for cardiovascular disease, and plasma triglycerides (TGs) correlate strongly with plasma apolipoprotein C-III (ApoC-III) levels. Antisense oligonucleotides (ASOs) for ApoC-III reduce plasma TGs in primates and mice, but the underlying mechanism of action remains controversial. We determined that a murine-specific ApoC-III-targeting ASO reduces fasting TG levels through a mechanism that is dependent on low-density lipoprotein receptors (LDLRs) and LDLR-related protein 1 (LRP1). ApoC-III ASO treatment lowered plasma TGs in mice lacking lipoprotein lipase (LPL), hepatic heparan sulfate proteoglycan (HSPG) receptors, LDLR, or LRP1 and in animals with combined deletion of the genes encoding HSPG receptors and LDLRs or LRP1. However, the ApoC-III ASO did not lower TG levels in mice lacking both LDLR and LRP1. LDLR and LRP1 were also required for ApoC-III ASO-induced reduction of plasma TGs in mice fed a high-fat diet, in postprandial clearance studies, and when ApoC-III-rich or ApoC-III-depleted lipoproteins were injected into mice. ASO reduction of ApoC-III had no effect on VLDL secretion, heparin-induced TG reduction, or uptake of lipids into heart and skeletal muscle. Our data indicate that ApoC-III inhibits turnover of TG-rich lipoproteins primarily through a hepatic clearance mechanism mediated by the LDLR/LRP1 axis. PMID:27400128

  5. Phenotypes of hypertriglyceridemia caused by excess very-low-density lipoprotein

    NARCIS (Netherlands)

    Sniderman, A.D.; Tremblay, A.; Graaf, J. de; Couture, P.

    2012-01-01

    OBJECTIVE: To characterize the composition of very-low-density lipoprotein (VLDL) particles and the proportion of VLDL to total apolipoprotein B (apoB) particles in patients with hypertriglyceridemia caused by excess VLDL. METHODS: Subjects were selected from 2023 consecutive patients attending the

  6. High-density lipoproteins: a novel therapeutic target for cardiovascular disease

    Directory of Open Access Journals (Sweden)

    TS Mohamed Saleem

    2011-01-01

    Full Text Available TS Mohamed Saleem1, PV Sandhya Rani1, K Gauthaman21Department of Pharmacology, Annamacharya College of Pharmacy, New Boyanapalli, Andhrapradesh, India; 2Department of Drug Technology, Faculty of Medical Technology, Derna, LibyaAbstract: Cardiovascular disease has a high rate of mortality in both Western and developing countries. Atherosclerosis and generation of reactive oxygen species through oxidative stress is the major risk factor for cardiovascular disease. Atherothrombosis with low levels of high-density lipoprotein (HDL and high levels of low-density lipoprotein is a major risk factor for atherosclerosis-induced cardiovascular disease. Lipid-lowering drugs like statins, niacin, fibrates, and some newer agents, ie, the apolipoprotein A-I mimetics and the cholesteryl ester transfer protein inhibitors, not only increase HDL levels but are also effective in reducing key atherogenic lipid components, including triglyceride-rich lipoproteins. The aim of this review is to discuss the accumulating evidence suggesting that HDL possesses a diverse range of biological actions, and that increasing HDL levels by drug treatment may be beneficial in the prevention of cardiovascular disease.Keywords: cardiovascular disease, lipoproteins, statins, apolipoprotein, atherosclerosis

  7. Spectroscopic studies on the modifications of lipoproteins by human myeloperoxidase - implications for atherosclerosis

    International Nuclear Information System (INIS)

    The mortality as a consequence of atherosclerosis is the major cause of death in the developed world and a wealth of evidence now indicates that low density lipoprotein must be modified in order to promote atherosclerosis. This modification may involve hypochlorous acid, released by the enzyme myeloperoxidase which catalyses the reaction of hydrogen peroxide with chloride ions. It was shown here that hypochlorous acid is produced in micromolar concentrations and is rapidly consumed by low density lipoprotein in a concentration dependent manner. The production of hypochlorous acid by the myeloperoxidase/hydrogen peroxide/chloride-system was accompanied by concomitant alterations of low density lipoprotein as detected by dynamic light scattering, fluorescence of a surface lipid label, native tryptophan fluorescence, liquid chromatography/mass spectrometry of phosphatidylcholines and UV absorption spectroscopy. It was shown that all components of the myeloperoxidase/hydrogen peroxide/chloride-system have rate determining effects on lipoprotein modification. Furthermore the kinetics of the decrease of tryptophan fluorescence was used to compare the effectiveness of MPO inhibitors that block production of hypochlorous acid with compounds that act as hypochlorous acid traps. Summarizing, the results of this study in turn provide important information required for the study of oxidative damage in the pathogenesis of atherosclerosis by myeloperoxidase in vivo. (author)

  8. Nevirapine Increases High-Density Lipoprotein Cholesterol Concentration by Stimulation of Apolipoprotein A-I Production

    NARCIS (Netherlands)

    R. Franssen; R.R. Sankatsing; E. Hassink; B. Hutten; M.T. Ackermans; K. Brinkman; R. Oesterholt; A. Arenas-Pinto; S.P. Storfer; J.J. Kastelein; H.P. Sauerwein; P. Reiss; E.S. Stroes

    2009-01-01

    Objective-The purpose of this study was to investigate the mechanism by which the nonnucleoside reverse transcriptase inhibitor (NNRTI) nevirapine (NVP) increases high-density lipoprotein cholesterol (HDLc) in treatment-experienced human immunodeficiency virus-1 (HIV-1)-infected patients. Methods an

  9. Studies on the metabolism and possible mechanisms of atherogenesis of lipoprotein (a)

    International Nuclear Information System (INIS)

    The mechanisms of atherogenesis are under intensive clinical and experimental investigation. It is commonly accepted that lipoproteins play a major role in atherogenesis. The results of several clinical studies suggest that lipoprotein(a) [Lp(a)] represents an independent risk factor for atherosclerosis. In order to obtain information on the physiological and pathological role of LP(a), studies were undertaken to investigate the metabolism, removal sites, and possible atherogenic mechanism of Lp(a). It was found that Lp(a) is not metabolic product of other apoprotein B containing lipoproteins, but appears to be synthesized as a separate lipoprotein. The turnover parameters of Lp(a) resemble those of LDL. Binding studies of Lp(a) with cultured human fibroblasts demonstrated that Lp(a) is bound by the B-E receptor. After binding, Lp(a) is internalized and inhibits cellular cholesterol synthesis. In the presence of dextran sulfate or antibodies to the specific Lp(a) apoprotein or apoprotein B, Lp(a) is avidly taken up by macrophages. A similar mechanism might be responsible for the atherogenic effect of Lp(a). (Author)

  10. Extreme lipoprotein(a) levels and risk of myocardial infarction in the general population

    DEFF Research Database (Denmark)

    Kamstrup, Pia R; Benn, Marianne; Tybjaerg-Hansen, Anne;

    2008-01-01

    of absolute risk estimates in the general population. We tested the hypothesis that extreme lipoprotein(a) levels predict MI in the general population, measuring levels shortly after sampling, correcting for regression dilution bias, and calculating hazard ratios and absolute risk estimates....

  11. Acute effects of moderate exercise on serum lipids, lipoproteins and apolipoproteins in sedentary young women.

    Science.gov (United States)

    Imamura, H; Katagiri, S; Uchid, K; Miyamoto, N; Nakano, H; Shirota, T

    2000-12-01

    1. The aim of the present study was to examine the effects of moderate exercise on serum lipids, lipoproteins and apolipoproteins in seven sedentary young women under controlled conditions. 2. The subjects exercised on separate days for 30 or 60 min at an intensity of 60% of maximal oxygen uptake on a cycle ergometer. Total cholesterol, triglycerides, high-density lipoprotein-cholesterol (HDL-C), HDL2-C, HDL3-C, low-density lipoprotein-cholesterol, apolipoproteins A-I, A-II and B were measured in the serum at the end of the 60 min rest period before each exercise, immediately after the performance of each exercise and at 30 min and 1, 2 and 24 h after each exercise. 3. The results showed that there were no significant differences between the pre- and postexercise samples for any of the parameters tested. 4. The results of the present study suggest that a single bout of exercise designed to simulate a typical training workout has no noticeable effect on serum lipids, lipoproteins and apolipoproteins in normal sedentary young women who have normal lipid profiles, are in the follicular phase of their menstrual cycle and who consume a relatively low-fat diet. PMID:11117233

  12. Imaging of hepatic low density lipoprotein receptors by radionuclide scintiscanning in vivo.

    Science.gov (United States)

    Huettinger, M; Corbett, J R; Schneider, W J; Willerson, J T; Brown, M S; Goldstein, J L

    1984-12-01

    The low density lipoprotein (LDL) receptor mediates the cellular uptake of plasma lipoproteins that are derived from very low density lipoproteins (VLDL). Most of the functional LDL receptors in the body are located in the liver. Here, we describe a radionuclide scintiscanning technique that permits the measurement of LDL receptors in the livers of intact rabbits. 123I-labeled VLDL were administered intravenously, and scintigraphic images of the liver and heart were obtained at intervals thereafter. In seven normal rabbits, radioactivity in the liver increased progressively between 1 and 20 min after injection, while radioactivity in the heart (reflecting that in plasma) decreased concomitantly. In Watanabe-heritable hyperlipidemic rabbits, which lack LDL receptors on a genetic basis, there was little uptake of 123I-labeled VLDL into the liver and little decrease in cardiac radioactivity during this interval. These findings demonstrate that the LDL receptor is necessary for the hepatic uptake of VLDL-derived lipoproteins in the rabbit. Two conditions that diminish hepatic LDL receptor activity, cholesterol-feeding and prolonged fasting, also reduced the uptake of 123I-labeled VLDL in the liver as measured by scintiscanning. The data suggest that radionuclide scintiscanning can be used as a noninvasive method to quantify the number of LDL receptors expressed in the liver in vivo. PMID:6594702

  13. Mutation in apolipoprotein B associated with hypobetalipoproteinemia despite decreased binding to the low density lipoprotein receptor

    DEFF Research Database (Denmark)

    Benn, Marianne; Nordestgaard, Børge G; Jensen, Jan Skov;

    2005-01-01

    Mutations in apolipoprotein B (APOB) may reduce binding of low density lipoprotein (LDL) to the LDL receptor and cause hypercholesterolemia. We showed that heterozygotes for a new mutation in APOB have hypobetalipoproteinemia, despite a reduced binding of LDL to the LDL receptor. APOB R3480P...

  14. The HDL hypothesis : does high-density lipoprotein protect from atherosclerosis?

    NARCIS (Netherlands)

    Vergeer, Menno; Holleboom, Adriaan G; Kastelein, John J P; Kuivenhoven, Jan Albert

    2010-01-01

    There is unequivocal evidence of an inverse association between plasma high-density lipoprotein (HDL) cholesterol concentrations and the risk of cardiovascular disease, a finding that has led to the hypothesis that HDL protects from atherosclerosis. This review details the experimental evidence for

  15. Gold Nanoparticles Enhanced Microchip Capillary Electrophoresis for Detection of Serum Lipoprotein

    Institute of Scientific and Technical Information of China (English)

    WANG Hua; WANG DaXin; CAO Li; CHEN Xia

    2009-01-01

    @@ We describe here the use of gold nanoparticles (AuNPs) in conjunction with chip-based capillary electrophoresis (CE) to improve the selectivity between lipoprotein fractions and increase the efficiency of the separation.AuNPs were added into the running buffer to manipulate solution and control the electroosmotic flow (EOF).

  16. Active lipoprotein precursors in the gram-positive eubacterium Lactococcus lactis

    NARCIS (Netherlands)

    Venema, R; Tjalsma, H; van Dijl, J.M; Leenhouts, K.; Buist, G; Venema, G

    2003-01-01

    Lipid-modified proteins play important roles at the interface between eubacterial cells and their environment. The importance of lipoprotein processing by signal peptidase II (SPase II) is underscored by the fact that this enzyme is essential for viability of the Gram-negative eubacterium Escherichi

  17. Characterization of Lipoprotein Composition and Function in Pediatric Psoriasis Reveals a More Atherogenic Profile.

    Science.gov (United States)

    Tom, Wynnis L; Playford, Martin P; Admani, Shehla; Natarajan, Balaji; Joshi, Aditya A; Eichenfield, Lawrence F; Mehta, Nehal N

    2016-01-01

    Psoriasis is associated with increased cardiovascular disease in adults, but the risk profile of children with psoriasis remains to be fully characterized. We measured lipoprotein composition and function in 44 patients with pediatric psoriasis and 44 age- and sex-matched healthy controls, using nuclear magnetic resonance spectroscopy and a validated ex vivo assay of high-density lipoprotein cholesterol efflux capacity. The mean age of the patients was 13 years and the population was ethnically diverse. Children with psoriasis had higher waist-to-hip ratios (0.85 vs. 0.80; P psoriasis was associated with higher apolipoprotein B concentrations (72.4 vs. 64.6; P = 0.02), decreased large high-density lipoprotein particles (5.3 vs. 6.7; P psoriasis have a more atherogenic cardiometabolic risk profile, with evidence of insulin resistance and lipoprotein dysfunction by particle size, number, and functional assessment. These findings may provide a basis for the observed link later in life between psoriasis and cardiovascular disease, and support the need to screen and educate young patients to minimize later complications.

  18. Induction of oxygen free radical generation in human monocytes by lipoprotein(a)

    DEFF Research Database (Denmark)

    Riis Hansen, P; Kharazmi, A; Jauhiainen, M;

    1994-01-01

    The mechanism behind the association of elevated plasma lipoprotein(a) [Lp(a)] levels with atherosclerotic disease is unknown. In the present study, Lp(a) induced generation of oxygen free radicals by monocytes from selected healthy individuals in vitro. This observation may provide a link between...

  19. Familial lipoprotein lipase-activity deficiency: study of total body fatness and subcutaneous fat tissue distribution.

    Science.gov (United States)

    Brun, L D; Gagné, C; Julien, P; Tremblay, A; Moorjani, S; Bouchard, C; Lupien, P J

    1989-10-01

    Total body fatness and subcutaneous fat tissue distribution were evaluated in 19 hyperchylomicronemic patients. Eleven were males, aged 10 to 57 years, and eight were females, aged 13 to 46 years. Familial lipoprotein-lipase-activity deficiency was diagnosed by the absence of lipoprotein-lipase activity in the plasma withdrawn ten and 20 minutes after intravenous injection of ten units of heparin per kilogram of body weight. The 19 patients had skin-fold measurements for evaluation of subcutaneous fat distribution. Fifteen also underwent body density measurements by underwater weighing. Percent body fat was calculated from body density. These anthropometric data were plotted against the regression curves of 1638 normal controls of both sexes (aged 10 to 54 years) for fat tissue weight, percent body fat, subcutaneous fat/total fat mass ratio and trunk/extremity skin-fold ratio. Impairments in the process of building fat tissue reserves could not be shown in the 19 hyperchylomicronemic patients, in spite of the absence of lipoprotein-lipase activity in their postheparin plasma. It is hypothesized that normal fat tissue mass in these patients could be due partly to de novo synthesis of fatty acids by adipocytes, hydrolysis of plasma triglycerides by hepatic lipase, and/or contribution of a specific fat-tissue lipase to the catabolism of plasma triglyceride-rich lipoproteins.

  20. Moderate alcohol consumption and lipoprotein-associated phospholipase A2 activity

    NARCIS (Netherlands)

    Beulens, J.W.J.; Berg, R. van den; Kok, F.J.; Helander, A.; Vermunt, S.H.F.; Hendriks, H.F.J.

    2008-01-01

    Background and aims: To investigate the effect of moderate alcohol consumption on lipoprotein-associated phospholipase A2 activity, markers of inflammation and oxidative stress and whether these effects are modified by BMI. Methods and results: Eleven lean (BMI: 18.5-25 kg/m2) and 9 overweight (BMI

  1. Phenotype of heterozygotes for low-density lipoprotein receptor mutations identified in different background populations

    DEFF Research Database (Denmark)

    Tybjaerg-Hansen, Anne; Jensen, Henrik Kjaerulf; Benn, Marianne;

    2005-01-01

    The effect of mutations on phenotype is often overestimated because of ascertainment bias. We determined the effect of background population on cholesterol phenotype associated with specific mutations in the low-density lipoprotein (LDL) receptor and the relative importance of background population...

  2. Lipoprotein lipase gene polymorphisms and the risk of target vessel revascularization after percutaneous coronary intervention

    NARCIS (Netherlands)

    Monraats, Pascalle S; Rana, Jamal S; Nierman, Melchior C; Pires, Nuno M M; Zwinderman, Aeilko H; Kastelein, John J P; Kuivenhoven, Jan Albert; de Maat, Moniek P M; Rittersma, Saskia Z H; Schepers, Abbey; Doevendans, Pieter A F; de Winter, Robbert J; Tio, René A; Frants, Rune R; Quax, Paul H A; van der Laarse, Arnoud; van der Wall, Ernst E; Jukema, J Wouter

    2005-01-01

    OBJECTIVES: We sought to identify polymorphisms in genes that predispose to restenosis. BACKGROUND: Variations in the lipoprotein lipase (LPL) gene have been implicated in a number of pathophysiologic conditions associated with coronary heart disease. The present study examines the impact of polymor

  3. The relationship between lipoprotein lipase-447C/G genepolymorphism and cerebral infarction in the elderly

    Institute of Scientific and Technical Information of China (English)

    胡晓雁

    2013-01-01

    Objective To explore the relationship between the lipoprotein lipase(LPL)-447C/G gene polymorphism and cerebral infarction in the elderly. Methods This was a case-control study,which enrolled 206 cases with cerebral infarction in the elderly and 203 elderly

  4. Expression of human apolipoprotein B and assembly of lipoprotein(a) in transgenic mice

    Energy Technology Data Exchange (ETDEWEB)

    Callow, M.J.; Stoltzfus, L.J.; Rubin, E.M. [Lawrence Berkeley Lab., CA (United States); Lawn, R.M. [Stanford Univ., CA (United States)

    1994-03-15

    The atherogenic macromolecule lipoprotein(a) [Lp(a)] has resisted in vivo analyses partly because it is found in a limited number of experimental animals. Although transgenic mice expressing human apolipoprotein (a) [apo(a)] have previously been described, they failed to assemble Lp(a) particles because of the inability of human apo(a) to associate with mouse apolipoprotein B (apoB). The authors isolated a 90-kilobase P1 phagemid containing the human apoB gene and with this DNA generated 13 lines of transgenic mice of which 11 expressed human apoB. The human apoB transcript was expressed and edited in the liver of the transgenic mice. Plasma concentrations of human apoB, as well as low density lipoprotein (LDL), were related to transgene copy number; the transgenic line with the most copies of human apoB had a >4-fold increase in LDL cholesterol compared with nontransgenics and a lipoprotein profile similar to that of humans. When human apoB and apo(a) transgenic mice were bred together, plasma apo(a) in mice expressing both human proteins was tightly associated with lipoproteins in the LDL density region. These studies demonstrate the successful expression of human apoB and the efficient assembly of Lp(a) in mice.

  5. Darapladib, a lipoprotein-associated phospholipase A2 inhibitor, in diabetic macular edema

    DEFF Research Database (Denmark)

    Staurenghi, Giovanni; Ye, Li; Magee, Mindy H;

    2015-01-01

    PURPOSE: To investigate the potential of lipoprotein-associated phospholipase A2 inhibition as a novel mechanism to reduce edema and improve vision in center-involved diabetic macular edema (DME). DESIGN: Prospective, multicenter, randomized, double-masked, placebo-controlled phase IIa study. PAR...

  6. Lipoprotein Lipase and PPAR Alpha Gene Polymorphisms, Increased Very-Low-Density Lipoprotein Levels, and Decreased High-Density Lipoprotein Levels as Risk Markers for the Development of Visceral Leishmaniasis by Leishmania infantum

    Directory of Open Access Journals (Sweden)

    Márcia Dias Teixeira Carvalho

    2014-01-01

    Full Text Available In visceral leishmaniasis (VL endemic areas, a minority of infected individuals progress to disease since most of them develop protective immunity. Therefore, we investigated the risk markers of VL within nonimmune sector. Analyzing infected symptomatic and, asymptomatic, and noninfected individuals, VL patients presented with reduced high-density lipoprotein cholesterol (HDL-C, elevated triacylglycerol (TAG, and elevated very-low-density lipoprotein cholesterol (VLDL-C levels. A polymorphism analysis of the lipoprotein lipase (LPL gene using HindIII restriction digestion (N = 156 samples (H+ = the presence and H− = the absence of mutation revealed an increased adjusted odds ratio (OR of VL versus noninfected individuals when the H+/H+ was compared with the H−/H− genotype (OR = 21.3; 95% CI = 2.32–3335.3; P = 0.003. The H+/H+ genotype and the H+ allele were associated with elevated VLDL-C and TAG levels (P < 0.05 and reduced HDL-C levels (P < 0.05. An analysis of the L162V polymorphism in the peroxisome proliferator-activated receptor alpha (PPARα gene (n = 248 revealed an increased adjusted OR when the Leu/Val was compared with the Leu/Leu genotype (OR = 8.77; 95% CI = 1.41–78.70; P = 0.014. High TAG (P = 0.021 and VLDL-C (P = 0.023 levels were associated with susceptibility to VL, whereas low HDL (P = 0.006 levels with resistance to infection. The mutated LPL and the PPARα Leu/Val genotypes may be considered risk markers for the development of VL.

  7. A Pressure-dependent Model for the Regulation of Lipoprotein Lipase by Apolipoprotein C-II*

    Science.gov (United States)

    Meyers, Nathan L.; Larsson, Mikael; Olivecrona, Gunilla; Small, Donald M.

    2015-01-01

    Apolipoprotein C-II (apoC-II) is the co-factor for lipoprotein lipase (LPL) at the surface of triacylglycerol-rich lipoproteins. LPL hydrolyzes triacylglycerol, which increases local surface pressure as surface area decreases and amphipathic products transiently accumulate at the lipoprotein surface. To understand how apoC-II adapts to these pressure changes, we characterized the behavior of apoC-II at multiple lipid/water interfaces. ApoC-II adsorption to a triacylglycerol/water interface resulted in large increases in surface pressure. ApoC-II was exchangeable at this interface and desorbed on interfacial compressions. These compressions increase surface pressure and mimic the action of LPL. Analysis of gradual compressions showed that apoC-II undergoes a two-step desorption, which indicates that lipid-bound apoC-II can exhibit at least two conformations. We characterized apoC-II at phospholipid/triacylglycerol/water interfaces, which more closely mimic lipoprotein surfaces. ApoC-II had a large exclusion pressure, similar to that of apoC-I and apoC-III. However, apoC-II desorbed at retention pressures higher than those seen with the other apoCs. This suggests that it is unlikely that apoC-I and apoC-III inhibit LPL via displacement of apoC-II from the lipoprotein surface. Upon rapid compressions and re-expansions, re-adsorption of apoC-II increased pressure by lower amounts than its initial adsorption. This indicates that apoC-II removed phospholipid from the interface upon desorption. These results suggest that apoC-II regulates the activity of LPL in a pressure-dependent manner. ApoC-II is provided as a component of triacylglycerol-rich lipoproteins and is the co-factor for LPL as pressure increases. Above its retention pressure, apoC-II desorbs and removes phospholipid. This triggers release of LPL from lipoproteins. PMID:26026161

  8. Genomic determinants of triglyceride and cholesterol distribution into lipoprotein fractions in the rat.

    Directory of Open Access Journals (Sweden)

    Miloslava Hodúlová

    Full Text Available The plasma profile of major lipoprotein classes and its subdivision into particular fractions plays a crucial role in the pathogenesis of atherosclerosis and is a major predictor of coronary artery disease. Our aim was to identify genomic determinants of triglyceride and cholesterol distribution into lipoprotein fractions and lipoprotein particle sizes in the recombinant inbred rat set PXO, in which alleles of two rat models of the metabolic syndrome (SHR and PD inbred strains segregate together with those from Brown Norway rat strain. Adult male rats of 15 PXO strains (n = 8-13/strain and two progenitor strains SHR-Lx (n = 13 and BXH2/Cub (n = 18 were subjected to one-week of high-sucrose diet feeding. We performed association analyses of triglyceride (TG and cholesterol (C concentrations in 20 lipoprotein fractions and the size of major classes of lipoprotein particles utilizing 704 polymorphic microsatellite markers, the genome-wide significance was validated by 2,000 permutations per trait. Subsequent in silico focusing of the identified quantitative trait loci was completed using a map of over 20,000 single nucleotide polymorphisms. In most of the phenotypes we identified substantial gradient among the strains (e.g. VLDL-TG from 5.6 to 66.7 mg/dl. We have identified 14 loci (encompassing 1 to 65 genes on rat chromosomes 3, 4, 7, 8, 11 and 12 showing suggestive or significant association to one or more of the studied traits. PXO strains carrying the SHR allele displayed significantly higher values of the linked traits except for LDL-TG and adiposity index. Cholesterol concentrations in large, medium and very small LDL particles were significantly associated to a haplotype block spanning part of a single gene, low density lipoprotein receptor-related protein 1B (Lrp1b. Using genome-wide association we have identified new genetic determinants of triglyceride and cholesterol distribution into lipoprotein fractions in the recombinant

  9. Auxin physiology of the tomato mutant diageotropica

    Science.gov (United States)

    Daniel, S. G.; Rayle, D. L.; Cleland, R. E.

    1989-01-01

    The tomato (Lycopersicon esculentum, Mill.) mutant diageotropica (dgt) exhibits biochemical, physiological, and morphological abnormalities that suggest the mutation may have affected a primary site of auxin perception or action. We have compared two aspects of the auxin physiology of dgt and wild-type (VFN8) seedlings: auxin transport and cellular growth parameters. The rates of basipetal indole-3-acetic acid (IAA) polar transport are identical in hypocotyl sections of the two genotypes, but dgt sections have a slightly greater capacity for IAA transport. 2,3,5-Triiodobenzoic acid and ethylene reduce transport in both mutant and wild-type sections. The kinetics of auxin uptake into VFN8 and dgt sections are nearly identical. These results make it unlikely that an altered IAA efflux carrier or IAA uptake symport are responsible for the pleiotropic effects resulting from the dgt mutation. The lack of auxin-induced cell elongation in dgt plants is not due to insufficient turgor, as the osmotic potential of dgt cell sap is less (more negative) than that of VFN8. An auxin-induced increase in wall extensibility, as measured by the Instron technique, only occurs in the VFN8 plants. These data suggest dgt hypocotyls suffer a defect in the sequence of events culminating in auxin-induced cell wall loosening.

  10. Induction of drought tolerant mutants of rice

    International Nuclear Information System (INIS)

    The ultimate goal of crop breeding is to develop varieties with a high yield potential and desirable agronomic characteristics. In Egypt, the most important qualities sought by breeders have been high yield potential, resistance to major diseases and insects, and improved grain and eating quality. However, breeding efforts should concentrate on varieties with the potential to minimize yield losses under unfavorable conditions such as drought, and to maximize yields when conditions are favorable. Rice (Oryza sativa L.) in Egypt is completely irrigated and a significant portion of the rice cultivated area is subject to water deficit resulting from an inadequate or insufficient irrigation supply. Drought tolerance is a complex trait in that it results from the interaction of histological and physiological characters of plant with environmental factors, both above-ground and under-ground. Accordingly, root characters are closely related to drought tolerance. Little attention has been paid in Egyptian breeding programs to root characters and their relation to shoot characters. Furthermore, induced mutations are considered as one of the most important methods to induce useful mutants, especially with improved root characters, to overcome the drought problem. The present investigation aimed to study the effect of different doses of gamma rays on several characters of three Egyptian rice varieties, i.e. 'Giza 171', 'Giza 175' and 'Giza 176' and to induce one or more mutants possessing drought tolerance

  11. Indy mutants: live long and prosper

    Directory of Open Access Journals (Sweden)

    Stewart eFrankel

    2012-02-01

    Full Text Available Indy encodes the fly homologue of a mammalian transporter of di and tricarboxylatecomponents of the Krebs cycle. Reduced expression of fly Indy or two of the C. elegansIndy homologs leads to an increase in life span. Fly and worm tissues that play key roles inintermediary metabolism are also the places where Indy genes are expressed. One of themouse homologs of Indy (mIndy is mainly expressed in the liver. It has been hypothesizedthat decreased INDY activity creates a state similar to caloric restriction (CR. Thishypothesis is supported by the physiological similarities between Indy mutant flies on highcalorie food and control flies on CR, such as increased physical activity and decreases inweight, egg production, triglyceride levels, starvation resistance, and insulin signaling. Inaddition, Indy mutant flies undergo changes in mitochondrial biogenesis also observed inCR animals. Recent findings with mIndy knockout mice support and extend the findingsfrom flies. mIndy-/- mice display an increase in hepatic mitochondrial biogenesis, lipidoxidation and decreased hepatic lipogenesis. When mIndy-/- mice are fed high calorie foodthey are protected from adiposity and insulin resistance. These findings point to INDY as apotential drug target for the treatment of metabolic syndrome, type 2 diabetes and obesity.

  12. Flower morphology of Dendrobium Sonia mutants

    International Nuclear Information System (INIS)

    Dendrobium Sonia is a commercial hybrid which is popular as cut flower and potted plant in Malaysia. Variability in flower is important for new variety to generate more demands and choices in selection. Mutation induction is a tool in creating variability for new flower color and shape. In vitro cultures of protocorm-like bodies (PLBs) were exposed to gamma ray at dose 35 Gy. Phenotypic characteristics of the flower were observed at fully bloomed flower with emphasis on shape and color. Approximately 2000 regenerated irradiated plants were observed and after subsequent flowering, 100 plants were finally selected for further evaluation. Most of the color and shape changes are expressed in different combinations of petal, sepal and lip of the flower. In this work, 11 stable mutants were found different at flower phenotype as compared to control. Amongst these, four mutant varieties with commercial potential has been named as Dendrobium 'SoniaKeenaOval', Dendrobium 'SoniaKeenaRadiant', Dendrobium 'SoniaKeenaHiengDing' and Dendrobium 'Sonia KeenaAhmadSobri'. In this paper, variations in flower morphology and flower color were discussed, giving emphasis on variations in flower petal shape. (author)

  13. nitrate non-utilizing (nit mutants

    Directory of Open Access Journals (Sweden)

    D. Aiuchi

    2008-01-01

    Full Text Available Mycotal and Vertalec are mass-produced fungal strains for insect control. Strain B-2, which was isolated in Japan, has high epiphytic ability on cucumber leaves. Protoplast fusion was performed using these strains of Verticillium lecanii to obtain new strains possessing useful characteristics as biological control agents (BCAs. We used nit mutants for visually selecting the protoplasts. Hybrid strains were subjected to molecular analysis using the polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLPs and arbitrarily primed-PCR (AP-PCR in order to determine protoplast fusion and/or genetic recombination. We detected 126, 44, and 4 hybrid strains from the combinations of Vertalec × Mycotal, B-2 × Mycotal, and B-2 × Vertalec, respectively. Morphological characteristics of hybrid strains differed from those of their parental nit mutants. Protoplast fusion of hybrid strains was confifi rmed in genomic DNA, but not in mitochondrial DNA (mtDNA. A uniform biased tendency of the DNA banding pattern was observed depending on the combination of parental strains. The molecular analysis also revealed genetic recombination. These results showed a novel method for producing hybrid strains of the entomopathogenic fungus V. lecanii.

  14. Auxin physiology of the tomato mutant diageotropical

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, S.G.; Rayle, D.L. (San Diego State Univ., CA (USA)); Cleland, R.E. (Univ. of Washington, Seattle (USA))

    1989-11-01

    The tomato (Lycopersicon esculentum, Mill.) mutant diageotropica (dgt) exhibits biochemical, physiological, and morphological abnormalities that suggest the mutation may have affected a primary site of auxin perception or action. We have compared two aspects of the auxin physiology of dgt and wild-type (VFN8) seedlings: auxin transport and cellular growth parameters. The rates of basipetal indole-3-acetic acid (IAA) polar transport are identical in hypocotyl sections of the two genotypes, but dgt sections have a slightly greater capacity for IAA transport. 2,3,5-Triiodobenzoic acid and ethylene reduce transport in both mutant and wild-type sections. The kinetics of auxin uptake into VFN8 and dgt sections are nearly identical. These results make it unlikely that an altered IAA efflux carrier or IAA uptake symport are responsible for the pleiotropic effects resulting from the dgt mutation. The lack of auxin-induced cell elongation in dgt plants is not due to insufficient turgor, as the osmotic potential of dgt cell sap is less (more negative) than that of VFN8. An auxin-induced increase in wall extensibility, as measured by the Instron technique, only occurs in the VFN8 plants. These data suggest dgt hypocotyls suffer a defect in the sequence of events culminating in auxin-induced cell wall loosening.

  15. Isolation of plasma lipoproteins by zonal ultracentrifugation in the B14 and B15 titanium rotors.

    Science.gov (United States)

    Wilcox, H G; Heimberg, M

    1970-01-01

    Lipoproteins were isolated from plasma of man, dog, rabbit, rat, and chicken by ultracentrifugation in continuous density gradients using the B14 titanium and B15 titanium zonal rotors. Both the VLDL and the LDL of human plasma were separated easily from the HDL and from the other more plentiful plasma proteins by centrifugation for only 1 or 2 hr in the B14 or B15 rotor, respectively. Satisfactory separation of the HDL from the more dense plasma proteins was not achieved with these rotors. The human LDL achieved isopycnic equilibrium (d 1.04) on prolonged periods (> 24 hr) of centrifugation in a sucrose-KBr density gradient. The pattern of distribution of cholesterol and phospholipid throughout the density gradient coincided with the pattern of distribution of the lipoprotein-protein measured spectrophotometrically or chemically. The concentration of cholesterol and phospholipid in the lipoproteins isolated by zonal ultracentrifugation agreed with analyses reported for lipoproteins isolated by sequential centrifugation in solutions of increasing density. The lipoproteins isolated by zonal ultracentrifugation were characterized further by their electrophoretic behavior. The fractions which were identified as the LDL (d 1.04-1.05) from all species migrated on paper as a beta-globulin; the LDL from plasma of dogs contained an additional component which has been designated as an alpha(2)-globulin. The fractions which were identified as the HDL from all species migrated as an alpha(1)-globulin. Reaction of human LDL with either rabbit antihuman beta-lipoprotein or rabbit antihuman serum resulted in a single immunodiffusion band. The S(f, 1.063) of the human LDL was calculated to be 6.0. When plasma from humans or rabbits was centrifuged in the B15 rotor, the HDL was not visible as a distinct peak and was not separable from the bulk of the more dense plasma proteins; when plasma from dogs or chickens was centrifuged under identical conditions, the HDL was clearly

  16. Mutant radiation-resistance alleles from the Escherichia coli Gamr444 mutant: Cloning and preliminary characterization

    International Nuclear Information System (INIS)

    Mutant alleles Gamr, which are able to increase the resistance to radiation of Escherichia coli wild-type cells, were cloned from the hyperradioresistant mutant Gamr444 on plasmid mini-Mu-vector MudII4042. The influence of recombinant plasmids on the sensitivity of wild-type and mutant (recA and htpR) cells to γ-irradiation was studied. It was shown that the enhanced resistance of the Gamr444 strain to radiation was caused by mutations of two different classes, dominant and recessive. The cloned recessive mutation gamr12 increases resistance to radiation only after homogenotization, that is, radiation-induced transfer from the plasmid to the chromosome, and it imposes constitutive expression of the heat-shock promoter htpG. Dominant mutant gamr alleles are active in the trans-position. A mutation-insertion into a chromosomal gene impaired by one of the dominant mutations, gamr18, was constructed. The insertion causes drastic cell radiosensitization on the recBC sbcB background and probably disturbs the RecF pathway of recombination and repair. Dominant plasmids of the second type lead to the RecA-independent inhibition of DNA postirradiation degradation. The radioprotective action of recessive and dominant gamr mutations is additive

  17. Inferring PDZ domain multi-mutant binding preferences from single-mutant data.

    Directory of Open Access Journals (Sweden)

    Elena Zaslavsky

    Full Text Available Many important cellular protein interactions are mediated by peptide recognition domains. The ability to predict a domain's binding specificity directly from its primary sequence is essential to understanding the complexity of protein-protein interaction networks. One such recognition domain is the PDZ domain, functioning in scaffold proteins that facilitate formation of signaling networks. Predicting the PDZ domain's binding specificity was a part of the DREAM4 Peptide Recognition Domain challenge, the goal of which was to describe, as position weight matrices, the specificity profiles of five multi-mutant ERBB2IP-1 domains. We developed a method that derives multi-mutant binding preferences by generalizing the effects of single point mutations on the wild type domain's binding specificities. Our approach, trained on publicly available ERBB2IP-1 single-mutant phage display data, combined linear regression-based prediction for ligand positions whose specificity is determined by few PDZ positions, and single-mutant position weight matrix averaging for all other ligand columns. The success of our method as the winning entry of the DREAM4 competition, as well as its superior performance over a general PDZ-ligand binding model, demonstrates the advantages of training a model on a well-selected domain-specific data set.

  18. Secretion of hepatitis C virus envelope glycoproteins depends on assembly of apolipoprotein B positive lipoproteins.

    Directory of Open Access Journals (Sweden)

    Vinca Icard

    Full Text Available The density of circulating hepatitis C virus (HCV particles in the blood of chronically infected patients is very heterogeneous. The very low density of some particles has been attributed to an association of the virus with apolipoprotein B (apoB positive and triglyceride rich lipoproteins (TRL likely resulting in hybrid lipoproteins known as lipo-viro-particles (LVP containing the viral envelope glycoproteins E1 and E2, capsid and viral RNA. The specific infectivity of these particles has been shown to be higher than the infectivity of particles of higher density. The nature of the association of HCV particles with lipoproteins remains elusive and the role of apolipoproteins in the synthesis and assembly of the viral particles is unknown. The human intestinal Caco-2 cell line differentiates in vitro into polarized and apoB secreting cells during asymmetric culture on porous filters. By using this cell culture system, cells stably expressing E1 and E2 secreted the glycoproteins into the basal culture medium after one week of differentiation concomitantly with TRL secretion. Secreted glycoproteins were only detected in apoB containing density fractions. The E1-E2 and apoB containing particles were unique complexes bearing the envelope glycoproteins at their surface since apoB could be co-immunoprecipitated with E2-specific antibodies. Envelope protein secretion was reduced by inhibiting the lipidation of apoB with an inhibitor of the microsomal triglyceride transfer protein. HCV glycoproteins were similarly secreted in association with TRL from the human liver cell line HepG2 but not by Huh-7 and Huh-7.5 hepatoma cells that proved deficient for lipoprotein assembly. These data indicate that HCV envelope glycoproteins have the intrinsic capacity to utilize apoB synthesis and lipoprotein assembly machinery even in the absence of the other HCV proteins. A model for LVP assembly is proposed.

  19. Modified lipoprotein-derived lipid particles accumulate in human stenotic aortic valves.

    Science.gov (United States)

    Lehti, Satu; Käkelä, Reijo; Hörkkö, Sohvi; Kummu, Outi; Helske-Suihko, Satu; Kupari, Markku; Werkkala, Kalervo; Kovanen, Petri T; Oörni, Katariina

    2013-01-01

    In aortic stenosis plasma lipoprotein-derived lipids accumulate in aortic valves. Here, we first compared the lipid compositions of stenotic aortic valves and atherosclerotic plaque cores. Both pathological tissues were found to be enriched in cholesteryl linoleate, a marker of extracellularly accumulated lipoproteins. In addition, a large proportion of the phospholipids were found to contain arachidonic acid, the common precursor of a number of proinflammatory lipid mediators. Next, we isolated and characterized extracellular lipid particles from human stenotic and non-stenotic control valves, and compared them to plasma lipoproteins from the same subjects. The extracellular valvular lipid particles were isolated from 15 stenotic and 14 non-stenotic aortic valves. Significantly more apoB-100-containing lipid particles were found in the stenotic than in the non-stenotic valves. The majority of the lipid particles isolated from the non-stenotic valves had sizes (23±6.2 nm in diameter) similar to those of plasma low density lipoprotein (LDL) (22±1.5 nm), while the lipid particles from stenotic valves were not of uniform size, their sizes ranging from 18 to more than 500 nm. The lipid particles showed signs of oxidative modifications, and when compared to isolated plasma LDL particles, the lipid particles isolated from the stenotic valves had a higher sphingomyelin/phosphatidylcholine -ratio, and also higher contents of lysophosphatidylcholine and unesterified cholesterol. The findings of the present study reveal, for the first time, that in stenotic human aortic valves, infiltrated plasma lipoproteins have undergone oxidative and lipolytic modifications, and become fused and aggregated. The generated large lipid particles may contribute to the pathogenesis of human aortic stenosis.

  20. Lipoprotein composition and serum cholesterol ester fatty acids in nonwesternized Melanesians.

    Science.gov (United States)

    Lindeberg, S; Nilsson-Ehle, P; Vessby, B

    1996-02-01

    In this study, the relationships between dietary fat [as measured by serum cholesterol ester fatty acids (CE-FA)], age, smoking, body mass index, and serum lipids were analyzed in 151 subsistence horticulturalists, aged 20-86 yr, from Kitava, Trobriand Islands, Papua New Guinea. Their diet consists of tubers, fruit, coconut, fish, and vegetables with a negligible influence of western food and alcohol. Total fat intake is low [21% of energy (en%)], while saturated fat intake from coconuts is high (17 en%, mainly lauric and myristic acid). In multivariate analysis, 11-43% of the variation of the serum lipoprotein composition was explained by CE-FA, age, and smoking habits. The proportion of CE20:5n-3 explained much of the variation of triglycerides (TG, negative relation) and high density lipoprotein-cholesterol (HDL-C, positive) in both sexes and serum apolipoprotein A1 (ApoA1, positive) in the males. CE16:0 was positively related to TG and negatively related to HDL-C and ApoA1 in both sexes, and in males it related negatively to total cholesterol (TC) and low density lipoprotein-cholesterol (LDL-C). In males, negative relationships were present between CE18:2n-6 and TC and between CE14:0 and serum lipoprotein(a). Smoking was independently associated with lower ApoA1 in both sexes and with lower HDL-C and higher TG, TC, LDL-C, and apolipoprotein B in males. In conclusion, marine n-3 fatty acids and linoleic acid showed the same potentially beneficial relationships with lipoproteins and apolipoproteins as in western populations. The relations of palmitic acid to serum lipids may be explained in terms of endogenous fat synthesis at a low-fat intake, rather than reflecting its relative intake.

  1. Neurobehavioral Mutants Identified in an ENU Mutagenesis Project

    Energy Technology Data Exchange (ETDEWEB)

    Cook, Melloni N. [University of Memphis; Dunning, Jonathan P [University of Memphis; Wiley, Ronald G [Vanderbilt University and Veterans Administration, Nashville, TN; Chesler, Elissa J [ORNL; Johnson, Dabney K [ORNL; Goldowitz, Daniel [University of Tennessee Health Science Center, Memphis

    2007-01-01

    We report on a behavioral screening test battery that successfully identified several neurobehavioral mutants among a large-scale ENU-mutagenized mouse population. Large numbers of ENU mutagenized mice were screened for abnormalities in central nervous system function based on abnormal performance in a series of behavior tasks. We developed and employed a high-throughput screen of behavioral tasks to detect behavioral outliers. Twelve mutant pedigrees, representing a broad range of behavioral phenotypes, have been identified. Specifically, we have identified two open field mutants (one displaying hyper-locomotion, the other hypo-locomotion), four tail suspension mutants (all displaying increased immobility), one nociception mutant (displaying abnormal responsiveness to thermal pain), two prepulse inhibition mutants (displaying poor inhibition of the startle response), one anxiety-related mutant (displaying decreased anxiety in the light/dark test), and one learning and memory mutant (displaying reduced response to the conditioned stimulus) These findings highlight the utility of a set of behavioral tasks used in a high throughput screen to identify neurobehavioral mutants. Further analysis (i.e., behavioral and genetic mapping studies) of mutants is in progress with the ultimate goal of identification of novel genes and mouse models relevant to human disorders as well as the identification of novel therapeutic targets.

  2. Serrated leaf mutant in mungbean (Vigna radiata (L) Wilczek)

    International Nuclear Information System (INIS)

    Dry dormant seeds of mungbean (Vigna radiata (L) Wilczek) were treated with gamma rays (15, 30 and 60 kR). The serrated leaf mutation was noticed in M2 of cultivar Pak 32 treated with 60 kR. Cf 14 plants, 3 showed the altered leaf structure and the others were normal. The feature of this mutant was the deep serration of leaflet margins. The mutant had large thick leaflets with prominent venation. The mutant bred true in the M3 and successive generation. Details of the morphological characteristics of the mutant are presented. The mutant exhibited slower growth particularly during the early stages of development, flowered later and attained shorter height. There was an increase in the number of pods, in seed weight and in seed protein content, but number of seed per pod was considerably reduced. The seed coat colour showed a change from green to yellowish green. In the mutant's flowers the stamina were placed much below the stigma level and the stigma sometimes protruded the corolla. Outcrossing of 4% recorded in some of the mutant lines revealed a reduced cleistogamy. The low number of seeds per pod in the mutant could be due to reduced pollen fertility. The mutant behaved as monogenic recessive. The symbols SL/sl are proposed for this allelic pair. The mutant may have use as a green manure crop because of its large foliage and for the breeders as a genetic marker

  3. Subfraction analysis of circulating lipoproteins in a patient with Tangier disease due to a novel ABCA1 mutation.

    Science.gov (United States)

    Murano, Takeyoshi; Yamaguchi, Takashi; Tatsuno, Ichiro; Suzuki, Masayo; Noike, Hirofumi; Takanami, Tarou; Yoshida, Tomoe; Suzuki, Mitsuya; Hashimoto, Ryuya; Maeno, Takatoshi; Terai, Kensuke; Tokuyama, Wataru; Hiruta, Nobuyuki; Schneider, Wolfgang J; Bujo, Hideaki

    2016-01-15

    Tangier disease, characterized by low or absent high-density lipoprotein (HDL), is a rare hereditary lipid storage disorder associated with frequent, but not obligatory, severe premature atherosclerosis due to disturbed reverse cholesterol transport from tissues. The reasons for the heterogeneity in atherogenicity in certain dyslipidemias have not been fully elucidated. Here, using high-performance liquid chromatography with a gel filtration column (HPLC-GFC), we have studied the lipoprotein profile of a 17-year old male patient with Tangier disease who to date has not developed manifest coronary atherosclerosis. The patient was shown to be homozygous for a novel mutation (Leu1097Pro) in the central cytoplasmic region of ATP-binding cassette transporter A1 (ABCA1). Serum total and HDL-cholesterol levels were 59mg/dl and 2mg/dl, respectively. Lipoprotein electrophoretic analyses on agarose and polyacrylamide gels showed the presence of massively abnormal lipoproteins. Further analysis by HPLC-GFC identified significant amounts of lipoproteins in low-density lipoprotein (LDL) subfractions. The lipoprotein particles found in the peak subfraction were smaller than normal LDL, were rich in triglycerides, but poor in cholesterol and phospholipids. These findings in an adolescent Tangier patient suggest that patients in whom these triglyceride-rich, cholesterol- and phospholipid-poor LDL-type particles accumulate over time, would experience an increased propensity for developing atherosclerosis. PMID:26616730

  4. Colony mutants of compatible nocardiae displaying variations in recombining capacity.

    Science.gov (United States)

    Brownell, G H; Walsh, R S

    1972-03-01

    Colonial morphology mutants of Nocardia erythropolis were isolated following ultraviolet (UV) irradiation. The alleles rou-1/smo-1 were located by recombinant analysis and found to be linked to previously mapped characters. On the basis of recombinant class type patterns obtained from various selective characters it was postulated that the rou-1 allele may span a region of unique nucleotides in the Mat-Ce genome. Recombination frequencies of rou-1 and smo-2 bearing mutants of the Mat-Ce mating type were found to differ by over 1000 fold. Attempts to demonstrate that low recombination frequencies produced by the Smo mutants were due to Rec(-) genes were unsuccessful. No increased sensitivity to either UV or X irradiation was observed by the Smo mutants. Acriflavine treatment of either Rou or Smo colony mutants failed to accelerate reversion or to alter the recombining potentials of the mutants.

  5. Mutant p53: multiple mechanisms define biologic activity in cancer

    Directory of Open Access Journals (Sweden)

    Michael Paul Kim

    2015-11-01

    Full Text Available The functional importance of p53 as a tumor suppressor gene is evident through its pervasiveness in cancer biology. The p53 gene is the most commonly altered gene in human cancer; however, not all genetic alterations are biologically equivalent. The majority of p53 alterations involve missense mutations that result in the production of mutant p53 proteins. Such mutant p53 proteins lack normal p53 function and may acquire novel functions, often with deleterious effects. Here, we review characterized mechanisms of mutant p53 gain of function in multiple model systems. In addition, we review mutant p53 addiction as emerging evidence suggests that tumors may depend on sustained mutant p53 activity for continued growth. We also discuss the role of p53 in stromal elements and their contribution to tumor initiation and progression. Lastly, current genetic mouse models of mutant p53 are reviewed and their limitations discussed.

  6. Mutant p53 in cell adhesion and motility.

    Science.gov (United States)

    Yeudall, W Andrew; Wrighton, Katharine H; Deb, Sumitra

    2013-01-01

    Pro-oncogenic properties of mutant p53 were investigated with the aid of migration assays, adhesion assays, and soft agar growth assays using cells stably expressing gain-of-function p53 mutants. To determine cell migration, "wound-healing" (scratch) assays and haptotactic (chamber) assays were used. H1299 cells expressing mutant p53 were found to migrate more rapidly than cells transfected with empty vector alone. Results from both types of migration assay were broadly similar. Migratory ability differed for different p53 mutants, suggesting allele-specific effects. Cells expressing p53 mutants also showed enhanced adhesion to extracellular matrix compare to controls. Furthermore, stable transfection of mutant p53-H179L into NIH3T3 fibroblasts was sufficient to allow anchorage-independent growth in soft agar. PMID:23150443

  7. Mutants of Cercospora kikuchii Altered in Cercosporin Synthesis and Pathogenicity.

    Science.gov (United States)

    Upchurch, R G; Walker, D C; Rollins, J A; Ehrenshaft, M; Daub, M E

    1991-10-01

    We have obtained spontaneous and UV-induced stable mutants, altered in the synthesis of cercosporin, of the fungal soybean pathogen Cercospora kikuchii. The mutants were isolated on the basis of colony color on minimal medium. The UV-induced mutants accumulated, at most, 2% of wild-type cercosporin levels on all media tested. In contrast, cercosporin accumulation by the spontaneous mutants was strongly medium regulated, occurring only on potato dextrose medium but at concentrations comparable to those produced by the wild-type strain. UV-induced mutants unable to synthesize cercosporin on any medium were unable to incite lesions when inoculated onto the soybean host. Cercosporin was reproducibly isolated from all inoculated leaves showing lesions. Although cercosporin involvement in disease has been indirectly suggested by many previous studies, this is the first report in which mutants blocked in cercosporin synthesis have been used to demonstrate that cercosporin is a crucial pathogenicity factor for this fungal genus.

  8. Mutants of Cercospora kikuchii altered in cercosporin synthesis and pathogenicity

    Energy Technology Data Exchange (ETDEWEB)

    Upchurch, R.G.; Walker, D.C.; Rollins, J.A.; Ehrenshaft, M.; Daub, M.E. (North Carolina State Univ., Raleigh (United States))

    1991-10-01

    The authors have obtained spontaneous and UV-induced stable mutants, altered in the synthesis of cercosporin, of the fungal soybean pathogen Cercospora kikuchii. The mutants were isolated on the basis of colony color on minimal medium. The UV-induced mutants accumulated, at most, 2% of wild-type cercosporin levels on all media tested. In contrast, cercosporin accumulation by the spontaneous mutants was strongly medium regulated, occurring only on potato dextrose medium but at concentrations comparable to those produced by the wild-type strain. UV-induced mutants unable to synthesize cercosporin on any medium were unable to incite lesions when inoculated onto the soybean host. Cercosporin was reproducibly isolated from all inoculated leaves showing lesions. Although cercosporin involvement in disease has been indirectly suggested by many previous studies, this is the first report in which mutants blocked in cercosporin synthesis have been used to demonstrate that cercosporin is a crucial pathogenicity factor for this fungal genus.

  9. Analysis of micro- and nano-structures of the corneal surface of Drosophila and its mutants by atomic force microscopy and optical diffraction.

    Directory of Open Access Journals (Sweden)

    Michail Kryuchkov

    Full Text Available Drosophila melanogaster is a model organism instrumental for numerous biological studies. The compound eye of this insect consists of some eight hundred individual ommatidia or facets, ca. 15 µm in cross-section. Each ommatidium contains eighteen cells including four cone cells secreting the lens material (cornea. High-resolution imaging of the cornea of different insects has demonstrated that each lens is covered by the nipple arrays--small outgrowths of ca. 200 nm in diameter. Here we for the first time utilize atomic force microscopy (AFM to investigate nipple arrays of the Drosophila lens, achieving an unprecedented visualization of the architecture of these nanostructures. We find by Fourier analysis that the nipple arrays of Drosophila are disordered, and that the seemingly ordered appearance is a consequence of dense packing of the nipples. In contrast, Fourier analysis confirms the visibly ordered nature of the eye microstructures--the individual lenses. This is different in the frizzled mutants of Drosophila, where both Fourier analysis and optical imaging detect disorder in lens packing. AFM reveals intercalations of the lens material between individual lenses in frizzled mutants, providing explanation for this disorder. In contrast, nanostructures of the mutant lens show the same organization as in wild-type flies. Thus, frizzled mutants display abnormal organization of the corneal micro-, but not nano-structures. At the same time, nipples of the mutant flies are shorter than those of the wild-type. We also analyze corneal surface of glossy-appearing eyes overexpressing Wingless--the lipoprotein ligand of Frizzled receptors, and find the catastrophic aberration in nipple arrays, providing experimental evidence in favor of the major anti-reflective function of these insect eye nanostructures. The combination of the easily tractable genetic model organism and robust AFM analysis represents a novel methodology to analyze development and

  10. Google: a narrativa de uma marca mutante

    Directory of Open Access Journals (Sweden)

    Elizete de Azevedo Kreutz

    2010-01-01

    Full Text Available As marcas mutantes já fazem parte de nossa realidade, embora ainda não totalmente percebidas e/ou aceitas como tal. O presente artigo busca refletir sobre a relevância dessas novas estratégias de comunicação e branding, identificando suas principais características. Para isso, utilizamos o método de estudo de caso, o Google, ancorado nos métodos de pesquisa bibliográfica e de internet. A escolha foi intencional, posto que a organização é referência em sua categoria, mecanismo de busca, e reflete essa estratégia comunicacional contemporânea. Como resultado, as informações obtidas nos possibilitam compreender essa tendência de comportamento de marca que busca a interação com seus públicos.

  11. [Effect of actinomycin D and cycloheximide on lipoproteins in blood serum and liver cytosol of rats under oxidative stress].

    Science.gov (United States)

    Kaliman, P A; Zahaĭko, A L

    2001-01-01

    The influence of protein synthesis inhibitors on rat lipoprotein content and composition under oxidative stress caused by cobalt chloride injection has been investigated in the present work. It has been concluded that apoprotein synthesis is very important process influencing on adaptive reactions under free-radical oxidation activation conditions. Co-administration of cobalt chloride and actinomycin D or cycloheximide (the inhibitors of the protein synthesis) has realy prevented hyperlipoproteinemia in many cases but hasn't influenced on lipoprotein oxidation. Pre-beta- and beta-lipoproteins were discussed to have mRNA pool in hepatocytes. PMID:12035534

  12. Study of Common Genetic Variant S447X in Lipoprotein Lipase and Its Association with Lipids and Lipoproteins in Type 2 Diabetic Patients.

    Science.gov (United States)

    Momin, A A; Bankar, M P; Bhoite, G M

    2016-07-01

    Elevated plasma triglyceride and non-esterified fatty acid concentrations may cause insulin resistance and type 2 diabetes mellitus. Lipoprotein lipase (LPL) is a rate-determining enzyme in lipid metabolism. A variant in the LPL gene has been identified which alters the penultimate amino acid Serine at 447 to a stop codon (S447X), and results in a truncated LPL molecule lacking the C-terminal dipeptide Ser-Gly. The present study was designed to evaluate the frequency of S447X variant in the LPL gene and its effect on the lipid and lipoprotein levels in type 2 diabetic subjects. The genotype frequency distributions of type 2 diabetes patients and controls were in Hardy-Weinberg equilibrium. Comparison of the genotype and allelic frequencies of S447X in subjects with type 2 diabetics compared to controls demonstrated no significant difference. In subjects with type 2 diabetics having hypertriglyceridemia (TG ≥ 150 mg/dl) compared to diabetics with TG level <150 mg/dl, significant difference in genotype frequency was found among these groups, while allelic frequency of X was significantly differed. Logistic regression analysis showed the negative association of LPL S447X variant with TG and VLDL cholesterol, while no association with total cholesterol, HDL cholesterol and LDL cholesterol was found. The lipid levels except for HDL cholesterol were found to be significantly lower in carriers for S447X than wild type in diabetes group. The decreased level of TG and TG rich lipoprotein in subjects with SNP S447X in LPL, predicts anti-atherogenic activity of carriers for S447X variant in general population as well as type 2 diabetic patients. PMID:27382199

  13. The association of the Clock 3111 T/C SNP with lipids and lipoproteins including small dense low-density lipoprotein: results from the Mima study

    Directory of Open Access Journals (Sweden)

    Takahashi Kaoru

    2010-10-01

    Full Text Available Abstract Background The clock molecule plays major roles in circadian rhythmicity and regulating lipid and glucose metabolism in peripheral organs. Disruption of the circadian rhythm can lead to cardiometabolic disorders. The existence of small dense low-density lipoprotein (sdLDL in the circulation, an abnormality of lipid metabolism, in part associated with lifestyle, is also one of risk parameters for cardiometabolic disorders. The 3111 T/C single nucleotide polymorphism (SNP of the Clock gene has been reported to be associated with lifestyle including morning/evening preference. We investigated whether the Clock 3111 T/C SNP may affect lipids and lipoproteins including sdLDL. Methods In 365 community-dwelling subjects (170 men and 195 women, mean age 63 ± 14 years, the 3111 T/C SNP was genotyped using a fluorescent allele-specific DNA primer assay system. The levels of sdLDL were measured with the electrophoretic separation of lipoproteins employing the Lipoprint system. Results The frequency of the Clock 3111 C allele was 0.14. The area of sdLDL did not differ between the subjects with obesity and those without. In carriers of T/T homozygotes, the area of sdLDL was significantly higher compared with carriers of the C allele (T/C or C/C (1.7 ± 3.4 vs. 0.8 ± 1.9%; p Clock 3111 T/C SNP (β = -0.114, p Conclusion Our findings indicated that the Clock 3111 T/C SNP might be associated with the existence of sdLDL.

  14. Some mutants in maize obtained by irradiation with thermal neutrons

    International Nuclear Information System (INIS)

    Irradiation was carried out at the Bucharest Institute of Atomic Physics and the National Laboratory Brookhaven, USA. A description is given of 22 genic mutants affecting leaf color, plant size, and branching capacity. Characteristics related to pollen fertility and the vegetative period were affected in all the mutants. Improvement of pollen fertility was attempted over four generations without success. The maize mutants obtained by irradiation may be considered as being without practical significance. (author). 7 figs., 1 tab. 11 ref

  15. Mutants of rabies viruses in skunks: immune response and pathogenicity.

    OpenAIRE

    Tolson, N D; Charlton, K M; Stewart, R B; Casey, G A; Webster, W A; Mackenzie, K.; Campbell, J. B.; Lawson, K. F.

    1990-01-01

    In studies to develop an oral rabies vaccine for wildlife, the immune response to and pathogenicity of two types of mutants of rabies viruses were examined. Forty-five small plaque mutants were selected from cultures of ERA rabies virus treated with 8-azaguanine or 5-fluorouracil and tested for pathogenicity in mice. Two of these mutants AZA 1 and AZA 2 (low pathogenicity in mice) were given to skunks by oral (bait), intestinal (endoscope) and intramuscular routes. Additionally, challenge vir...

  16. Induced mutants from dihaploid potatoes after pollen mother cell treatment.

    Science.gov (United States)

    Przewoźny, T; Schieder, O; Wenzel, G

    1980-05-01

    Microspore mother cells of dihaploid Solanum tuberosum plants were mutagenically treated during the stage of meiosis. Mutagenesis was performed either by irradiation with x- or γ-rays or by the application of nitrosomethylurethane or methylnitronitrosoguanidine. Then, by use of the anther culture technique, 913 functional plants and 442 untreated control plants were regenerated. From the exposed plants seven distinct mutants could be isolated, predominantly chlorophyll deficient lines, while from the controls no clear-cut mutants arose. One mutant turned out to be photomorphogenetic in addition to having a chlorophyll defect. In addition to the production of mutants the treatments significantly increased the frequency of multicellular structure formation from microspores.

  17. [Pigment composition and photosynthetic activity of pea chlorophyll mutants].

    Science.gov (United States)

    Ladygin, V G

    2003-01-01

    Pea chlorophyll mutants chlorotica 2004 and 2014 have been studied. The mutants differ from the initial form (pea cultivar Torsdag) in stem and leaf color (light green in the mutant 2004 and yellow-green in the mutant 2014), relative chlorophyll content (approximately 80 and 50%, respectively), and the composition of carotenoids: the mutant 2004 contains a significantly smaller amount of carotene but accumulates more lutein and violaxanthine; in the mutant 2014, the contents of all carotenoids are decreased proportionally to the decrease in chlorophyll content. It is shown that the rates of CO2 assimilation and oxygen production in the mutant chlorotica 2004 and 2014 plants are reduced. The quantum efficiency of photosynthesis in the mutants is 29-30% lower than in the control plants; in their hybrids, however, it is 1.5-2 higher. It is proposed that both the greater role of dark respiration in gas exchange and the reduced photosynthetic activity in chlorotica mutants are responsible for the decreased phytomass increment in these plants. On the basis of these results, the conclusion is drawn that the mutations chlorotica 2004 and 2014 affect the genes controlling the formation and functioning of various components of the photosynthetic apparatus. PMID:12942751

  18. plenty, a novel hypernodulation mutant in Lotus japonicus.

    Science.gov (United States)

    Yoshida, Chie; Funayama-Noguchi, Sachiko; Kawaguchi, Masayoshi

    2010-09-01

    Nitrogen fixation in nodules that contain symbiotic rhizobial bacteria enables legumes to thrive in nitrogen-poor soils. However, this symbiosis is energy consuming. Therefore, legumes strictly control nodulation at both local and systemic levels. Mutants deficient in such controls exhibit a range of phenotypes from non-nodulation to hypernodulation. Here, we isolated a novel hypernodulation mutant from the M(2) progeny derived from Lotus japonicus MG-20 seeds mutagenized by irradiation with a carbon ion beam. We named the mutant 'plenty' because it formed more nodules than the wild-type MG-20. The nodulation zone in the plenty mutant was wider than that in the wild type, but not as enhanced as those in other previously reported hypernodulation mutants such as har1, klv or tml of L. japonicus. Unlike these hypernodulation mutants, the plenty mutant developed nodules of the same size as MG-20. Overall, the plenty mutant exhibited a unique phenotype of moderate hypernodulation. However, a biomass assay indicated that this unique pattern of hypernodulation was a hindrance to host plant growth. The plenty mutant displayed some tolerance to external nitrates and a normal triple response to ethylene. Grafting experiments demonstrated that the root of plenty was responsible for its hypernodulation phenotype. Genetic mapping indicated that the PLENTY gene was located on chromosome 2.

  19. Analysis of canthaxanthin and related pigments from Gordonia jacobaea mutants.

    Science.gov (United States)

    de Miguel, T; Sieiro, C; Poza, M; Villa, T G

    2001-03-01

    A collection of 43 mutant strains of the bacterium Gordonia jacobaea was obtained by means of ethyl methanesulfonate treatment, and the strains were selected for their different pigmentation with respect to the wild-type strain. None of the mutants showed auxotrophy. They all showed good genetic stability and a growth rate similar to that of the parental strain. Canthaxanthin and other carotenoids from these mutants were extracted with acetone and ethanol and separated by high-performance liquid chromatography (HPLC). These HPLC analyses, together with spectrophotometric detection at 480 nm, revealed variations in the pigment contents of the different mutant strains. PMID:11312835

  20. Polarized secretion of newly synthesized lipoproteins by the Caco-2 human intestinal cell line.

    Science.gov (United States)

    Traber, M G; Kayden, H J; Rindler, M J

    1987-11-01

    Lipoprotein secretion by Caco-2 cells, a human intestinal cell line, was studied in cells grown on inserts containing a Millipore filter (0.45 micron), separating secretory products from the apical and basolateral membranes into separate chambers. Under these conditions, as observed by electron microscopy, the cells formed a monolayer of columnar epithelial cells with microvilli on the apical surface and tight junctions between cells. The electrical resistances of the cell monolayers were 250-500 ohms/cm2. Both 14C-labeled lipids and 35S-labeled proteins were used to assess lipoprotein secretion. After a 24-hr incubation with [14C]oleic acid, 60-80% of the secreted triglyceride (TG) was in the basolateral chamber; 40% of the TG was present in the d less than 1.006 g/ml (chylomicron + VLDL) fraction and 50% in the 1.006 less than d less than 1.063 g/ml (LDL) fraction. After a 4-hr incubation with [35S]methionine, apolipoproteins were found to be major secretory products with 75-100% secreted to the basolateral chamber. Apolipoproteins B-100, B-48, E, A-I, A-IV, and C-III were identified by immunoprecipitation. The d less than 1.006 g/ml fraction was found to contain all of the major apolipoproteins, while the LDL fraction contained primarily apoB-100 and apoE; the HDL (1.063 less than d less than 1.21 g/ml) fraction principally contained apoA-I and apoA-IV. Mn-heparin precipitated all of the [35S]methionine-labeled apoB-100 and B-48 and a majority of the other apolipoproteins, and 80% of the [14C]oleic acid-labeled triglyceride, but only 15% of the phospholipid, demonstrating that Caco-2 cells secrete triglyceride-rich lipoproteins containing apoB. Secretion of lipoproteins was dependent on the lipid content of the medium; prior incubation with lipoprotein-depleted serum specifically reduced the secretion of lipoproteins, while addition of both LDL and oleic acid to the medium maintained the level of apoB-100, B-48, and A-IV secretion to that observed in the control